Yes he is more gentle ,poor man took an overdose. But as u say he is bouncing back

There are lots of good books out there , its hard to chose but it depends on how much you want to spend and what exactly you are looking for .

Think dog by John Fisher is very much out of date now.
As has already been said , burn any Cm books.

General books that are informative and easy to read , I like Clever Dog by Sarah Whitehead and Dogs Secrets (What your dog wishes you knew) by David Ryan.

Books that are more specific ,

Canine body language - A photographic guide by Brenda Aloff.
Expensive and the photos are in black and white , but very good photos and written explanations .

How Dogs learn by Burch and Bailey. Explanations and definitions of Operant conditioning , Positive reinforcement and punishment etc , etc , Classical conditioining.
A lot of pennies dropped when I read it and if you are thinking of being a trainer then you really need to read it .

Clicker training book . Dont shoot the dog by karen pryor and also Click for joy by Melissa Alexander.

Patricia McConnells book . Other end of the Leash and For the Love of a dog (understanding emotion in you and yoiur best friend . I though these were good but did find them a bit hard going .

Oh Behave by jean Donaldson , a question and answer type of book about covering a wide range from training to behaviour and how to solve problems your dog might have . Interesting bit about genes and behaviour .

There is a book I'll recommend for selecting a breed. It's called "Choosing the Dog That's Right For You, The Good, The Bad, and The Furry" by Sam Stall.

Full of spot on profiles of our canine friends. With a sense of humor the author cites the best and worst typical breed behavior. Fun to read just for reference too.

Just finished reading "If a Dog's prayers were answered, bones would rain from the Sky" by Suzanne Clothier.
Absolutely loved it.
Her holistic approach really resonated with me and how I see our rl.ships with our dogs.

I also like Ian Dunbar's books a lot, despite these being pretty old now as well.