Changing light time at end of flower

Okay I'm a newbie. Someone suggested to me to lengthen the light cycle at the end of the flowering period. Would this help fatten up the flowers if u change back to 18-6the or more for the last 2 weeks to finish while flushing? I hope this isn't a stupid question but you have to start somewhere?

i would think the plants will try to go back into veg state, stopping THC production.

i wouldent do that. be carefull what you hear/ and read... not all of it is ture ..

Sounded crazy too me thats y i put the question out there.