Dogs - and random thoughts

I have two dogs. Flint who is a blue tri-coloured Border Collie and Mak who is a short-coated tri WSD (Working Sheep Dog).

Flint+Mak

Both Flint and Mak are first and foremost family pets. But being collies they are highly intelligent and need to have a job to channel their energy and enthusiasm for life.

Their job is to do agility.

Flint who is six years old competes at Kennel Club Grade 5.

Mak was born May 2013 and his training is coming on well. I hope Mak will start competing in Spring 2015.

     
Why do so many books about dog training omit an index?