Where's the proof that Kakashi has 1000 justus?

[Silverblade]

Kakashi the copy ninja, he is so good at it that He can even copy plot no jutsu and used it against tobi

I'll have to add to your green bar for that post. That probably explains Chapter 636.

 

[Stark]

He has shown various Fire Style, Earth Style and Water Style ninjutsu. Not to mention he learned Rasengan and has many Chidori variants.

 

[warlee]

I think he has the most fight after naruto and sasuke yet he showed like 3 copied. They are low level jutsu anyway so that won't change anything