Originally Posted by BlindEternities
you'd have to have negative AD to deal less damage than the same amount of AP
i know what you want to say, but your statement is mathematically incorrect.
with trinity force you just do 20.4 + 10% AD more dmg than with the same amout of AP with mystic shot (with lichbane/trinity)
but what you have to consider is the possible range of values for AD and AP
just look at this builds:
AP: 14665g - 662.5 AP
AD: 18022g - 407 AD
1. AP is cheaper
2. Look at the champion abilities tab.. 672
vs 293 essence flux; 779
.9 vs 302.5 arcane shift; 1113.75
vs 671 trueshot barrage; Mystic shot as we learned: 914,7
oh wait! EVERY skill does more damage with the AP build (this even holds true for maximized possible values)
There's a short period at the beginning of the game, where AD is indeed better than AP, when you have got no AP. If you finish lichbane as first/second item you have already enough AP that you are better off with AP (just tested empirical).
I just want to remind you, that I only share why I
(bold!) have switched to AP. If you like AD more and think it's better, I'm absolutely fine with it. But these are the facts.