Just wondering -
If someone ASKS for help in improving his/her skills -
I think it's a kindness to tell/show the person where alternate (better) techniques can be used.
It is a disservice to tell someone that something is wonderful when it isn't.
It is good to be accentuate the positive - but how can a person improve/change - if one has no idea of what is wrong or how the condition can be changed/improved?
It isn't so much "what is said" - as "how it's said"
If the person is fishing for compliments - find one and give it -
If the person truly wants to improve his/her work - then give suggestions IF ASKED FOR.