Both are right...Bubba stop yelling please (all caps).

Tho it is not wise to top in flower, it can be done very early and it will take an additional week or two to finish. It could also hermie. I know this because I have tried topping in flower and/or had an accident that topped the plant. It does not increase the amount of product at all.

" It does not increase the amount of product at all." Can also be said for topping in veg. You can make one hell of a bush tho which can be great for stealth purposes.........

Myself, I top for height control.