Hey, Amos! 'S up? ;-)

I have a friend who always says, "Hey" when he means "hello" or "How are you?" He'd drive you nuts. He's on this forum, but I am sworn not to reveal his name. He even answers the phone, "Hey" when you call him. He once sent me an email.

It said: Hey

I replied: Hey what?

He replied: Just hey.

I said: Hey to you to.

And so on....

But when will texting reduce the word "Hey" to just "HY" to save time?