I know, but still it's very slow and a boosting affix (similar to nadroji, crystalline, etc.) could be nice to have in order to focus-farm without taking chances. Let's say I have an eternal map and I need one more Enslaver kill to spawn the Mythic one: is it fair that I have no means to ensure (without paying) that I'll get it within that map to boost its drops?
Also free boost comes at random and "monster spawn" DOESN'T WORK on the floor you are getting into after the video (so you could waste your map). You can spam-load low level maps to wait the boost, yeah, but that's even more annoying.
And, apart from that, my suggestion is wider that just that: we need some new interesting high-floor items, because the game starts being boring after a while and the farm doesn't improve that much.