Typical "personal trainer" preaching this shit. Dont get me wrong, im NOT saying to throw the weight around but all the strict form crap is stupid. Unless your goal is to look like this guy. That said, I do think its important for a beginer to learn it so they dont kill themselves.
seriously why do gyms hire these guys?
I think that it's important on everything except presses cause locking out uses a lot of tris taking tension off the desired muscle and it's really not easier because if you go just shy of lock out you got the hard part over with and you dont have that little rest that comes with locking out either. I think you should always go faily slow(unless doiung a 225 rep out ) and always go down(hate those fags that bench 6 inches above their chest) all the way and get the full strech. But hey everybody is different and you should do what allows you to get then muscle working best and not what allows you to get the most weight up.
What you're saying is mostly true, but the point is: I didn't ask for your two cents.