I have exactly the same problem with my Brittany pup. It seems you are a member of a very large club .
I’m working on the theory that if I can get him to do nothing (as in become inactive) on command, he can’t get into trouble, so I‘m working on a stay/down command/whistle as being more urgent than recall (but am working on his recall too). Is this faulty thinking?

My girl seems to reach the point of no return when she sees the other dog or person. I have known her look back at me and ignore the recall command and carry on. I now take her into the park on a flexi lead and let her off where there is neither man nor beast in sight. However, I personally find it rather detracts from the pleasure of walking with and playing with my dog when I am constantly scanning the horizon for dogs etc.
If she does run off to play with another dog I find that when I then go to get her she dances around out of reach. But she will often go down on command and I can then get hold of her and put the lead on. I think to train down/stay on command is a good way of dealing with the problem if your dog will obey.
If, as you say, it finally all comes together does that mean I just have to carry on being vigilant while I wait for her to mature?

Also she is so clever that often when I recall her she looks around to check if there is another dog nearby. Even though I recall her regularly when there are no dogs around and treat her and release her. I suppose because inevitably at some time there will be another dog nearby this behaviour will never be extinguished.

Aw, don't be downhearted, I expect we all think that our pups will never behave, recall is quite a big thing to achieve if you think about it, especially when they are young and the world is so exciting!

I expect you do this, but do you make a big old fuss when he comes back? I used to jump up and down and squeal and generally make a twit of myself, but he used to love it when I did that, he used to grow two inches in height and look all proud of himself

You just have to make it more comfortable and pleasant for him to do what you ask rather than the other thing. Its so difficult, I know, but it does all come in the end. I don't know how old your dog is but he might just be having that teenage phase...

Times I have sat there 20 minutes waiting for his highness to decide to come back, we used to tie a long piece of rope to him so that we could stamp on it from a distance, we read that in a gundog training book. He never twigged how we could stop him running from 10' away. I thought it was dangerous but I was at my wit's end for a while.

Now he stops instantly if I shout 'wait' and his recall is very good 99.9% of the time, so take heart.

Hope some of this helps but at least you can congratulate yourself on having a friendly, outgoing and happy dog, so well done for that!

Yes she is naturally a very good natured dog and so far gets on with everyone. Her best friend is an Italian greyhound so not really matched in size but somehow she knows to be gentler and more careful with the little ones. She will be a year old next week so perhaps I am expecting too much of her too soon. Will try jumping up and down and getting really excited when she returns. I regularly make a fool of myself to further my dog training anyway.

LOL I jumped up and down with a happy, happy voice 'yay! Yay! Hooray for Archie Goooooood boy!' Its a wonder they didn't cart me off....

1 year old is about right for the teenage phase. It will come together.

What's funny is that when they get older and slow down you miss them being a bit loopy