Dog on Dog possible aggression. Sorry long post

Advice and suggestions appreciated. Sorry long post.
I have a wonderful smooth collie Tass who is 2 and a half. As a puppy she was well socialised and lives with 2 other dogs. For the last year I have been having a few problems with her. It stated with her being difficult on the lead when getting near other dogs. She started lunging at them barking and sounding aggressive. Off the lead she was fine then she started jumping on large dogs grabbing their ruffs and barking. This looks very aggressive but she has never done any damage and has very good bite inhibition and I am still not sure if this aggression based on fear, defence, over enthusiastic play, or something else. The last straw was when she did it to a dog on a lead. I try to stop her when with off lead dogs. The other dog usually has a go back and then they natrually break, if by the time I get to her they have not parted I get hold of her and drag her away appolagising. Most times the other dog is not worried about this but naturally the owner is. Her recall is good except when she seems to concentrate on a dog in the distance and then I really don’t think she even hears me. If this happens I know she is going to go over and be difficult. If she is not bothered by the other dogs her recall is fine. She has never been nasty to a smaller dog only same size or larger dogs. She seems to take exception to some collies, german shepherds and some golden retrievers, She is as good as gold with all puppies and small dogs. After her go at a dog on a lead I decided I needed professional help. I took her to a man who used to be a police dog trainer recommended by a friend and the local rescue home. He told me that I had unreasonable expectation to expect my dog to get on with all dogs and that my problem was that she did not understand what I wanted. So I went to see him for him to show me how to make her understand me. He did make sense in some of what he told and showed me but I did not agree with a lot he said and felt his methods were too harsh for my sensitive bitch. He said dogs were not sociable animals they only needed us and that it would be best not to mix with other dogs but replace this sociable outlet with stimulation from me and that to keep her on a lead and when we approached other dogs hold her lead very tight and march her past other dogs and make her take absolutely no notice of them and reprimand her is she so much as looked at them. Against my better judgement I did try this, not as fierce as he wanted, just keeping lead tight and marching her past dogs but it was a disaster. She got much worse stiffening and getting distressed at the sight of any dog.Back to the drawing board.
Next trainer a behaviourist was also a clicker trainer she said she was aggressive because she did not understand calming signals. Ttainer was very good and patient and taught me a lot about clicker training which I have used on my puppy and it works really well. It has helped with my bitch. She also had me walk up and down with my bitch with her and her stooge dog until my bitch made the right calming signals and calmed down. This does seem to of worked with her stooge dog but not with strange dogs.
Tried another trainer as wanted to do my Kennel Club Good Citizen tests and clicker trainer could not do this. She has said my bitch does use all the right calming signals is not afraid is not really aggressive just very bossy and provided the other owners drop the lead if Tass approached their dog should be no trouble. The reason for this is Tass is much more likley to have a go at a dog now that is walking in a straight line at heel or on a lead. Probably true but does not solve my problem. I would be very upset if a strange dog came up to my dog on a lead making what I perceived to be aggressive actions whether it meant them or not. I have got to get the recall totally under control. Her recall is so good as long as another dog she wants to have a go at is not in sight. She recalls from some dogs and then if I let her go she is fine with them. She is fine with 99% of dogs and we only have a problem occasionally so I do not want to keep her on a lead all her life but want to solve this problem. I am going to training with this new trainer on agility to help with the recall under stress which I hope will help. I also give her treats of hot dog sausages when we get near other dogs and if she does a good greeting she hits the jackpot and gets a whole handful. I am trying to get her to see meeting all other dogs as a good experience. Has any one any other suggestion that could help please

While I agree that dogs don`t need to make friends with other dogs, they do need to learn to be calm around them.
What you are doing with the treats is excellent, but how about asking her to look at you as well? Instead of worrying about the other dog?
I would also play with her and use the play article in your recall work as it sounds like she gets over-excited. Using toys when training gets the dog used to obeying commands when aroused. I find it very useful.
When she is calm and focussed on you round other dogs you could try walking with someone with well-socialised dogs? I find this teaches my dogs manners as they copy the other dog.

Has your bitch had her eye screened for CEA before she was 12 weeks old or since then ? Smooth Collies have one of the highest % of all the collies for CEA & it could be that her eyesight is not good.

Thanks for your helpful suggestions. When other dogs are around I do try to get her to look at me before getting her treats and she is getting better at this. I think you are right about getting over excited. She is a very reactive sensitive bitch who does seem to get over excited. Unfortunatley she does not like playing with toys. She chases after moving toys but does not pick them up or want to play tug. I am trying to get her interested in playing by using clicker training but she is not impressed but I will keep trying. I do try to look for people with well socialised dogs and am glad to sat she will often walk quietley and happily with other dogs and people it is just sometimes she gets uptight and nasty for no apparant reason I can see.
I am glad to say that I have had her eyes tested and luckily she and my other pup do not have CEA.

from what you tell us I think it wise to accept that your dog is aggressive, not “possibly” so. Although not at the top end of the aggression scale, it is a problem you obviously want to eliminate.

My summing up from what you say is that she is a “stroppy bitch”, a bossy young lady who is at the age when she thinks she rules the world. Not frightened or dominant, just downright bossy, nevertheless with aggression which will make your life difficult.

I believe you need to work on your relationship with your dog, don't think too much about her relationship with other dogs, although give her every opportunity to be exposed to other dogs, but not so that she can attack them.

It's her doing what you want that is important. At present she is doing what she wants. For the time being she should be called back to you whenever other dogs are in sight. Let her meet the other dogs but only in your presence, so that you have immediate input to correct any behavioural misdemeanours.

If you cannot do that because she doesn't respond correctly, keep her on lead in the presence of other dogs until you have built a relationship where she does what you tell her.

Police Dog Trainers, I wouldn't touch with a bargepole, and clicking away like mad ain't likely to help much either. It's you and your dog, you boss, she very good friend.

She sounds v like my girl Mia

I was gonna post lots of advice here, but I think with the people you have seen you have had too much advice already - some good and some bad
and it sounds like you have pretty good instincts for your girl too

I would recomend getting your hands on the book 'control unleashed' its great for anyone but it is specificaly for reactive, clicker trained, agility dogs. It explains things really well and gives you plenty of exercises to practise

I know it is difficult and you are both gonna have good and bad days - but it does get better if you work at it. - we are about a year ahead of you, not perfect yet but I have areas where I can walk Mia offlead and she is fine with the dogs she meets, some days she can be calm and let onlead dogs walk pretty close by her without reacting, and when she does react she gets over it much quicer

You sound like a v caring great owner commited to helping your girl. I look forward to hearing your progress, give me a yell any time if I can help in any way

Hi, I have the same problem with my dog. He often pounces in front of other dogs barking and growling at them especially if they are submissive. I suppose he could be a called a bully but he is a lovely dog and when he has got to know other dogs their owners say he has a lovely temperament. However, I have had a couple of really nasty incidences when other owners have been unnecessarily harsh to me. The other day my dog pounced in front of a dog and barked at it - he didn't go into his song and dance routine as I call it - he only barked a couple of times - anyway the owner (a man) swore at me constantly and really horribly and then began to step towards me menacingly and said that he would be aggressive towards me in a minute. I was terrified - I couldn't believe a man would speak to a woman (who he didn't know) like that. I hadn't provoked him or raised my voice whereas he was shouting and swearing at me the whole time. I am trying to correct my dog's habit but I'm like the woman in the Police Academy film with the little voice. I will persevere though.