Yep, in many cases you won't even use
str and that's why i'm pricing it so low. But i just feel that 2 pts is a bit too low for the opportunity. And wagonboyz have nice chances of getting to mellee and use this advantage. So, i'll stop on 3 pts right now and continue testing the grot special rule.
It's Grot's Life can make regular grots a solid option either. Cause they now become
dkok with their ignore ranged combat losses till the runtherd is still alive. Might be too much of a buff - must test. Though, it might force some assault-oriented or flamer-drop units on the opponent's side which is super-good for gameplay
imo 
But also it might force more ignore cover stuff which is super-lame