coloration of trichomes is actually past 'peak' potency. THC is mostly colorless, but what it breaks down into and is not as psychoactive is the amber you see.
this is more art than science, even though the above is true. you try to do what's best for the bulk... sometimes that means more amber up top while letting lower buds develop more. Without lab testing and ccomparing numerous results across different strains etc etc.. i wouldn't put too much weight into what any 1 person beleives. Apply the gist of it as best you can... experiement with early to late harvests and whatever gives the best high is the winner.
heck, there's no gaurantee it effects you the same as others. Look at Nyquil... most people go into a coma, others get hyper.