[Dire]

FAQs like these are not meant for solid winning long term player, as a solid winning longterm player would already have a good grasp on variance and general bankroll management. Recommending 20buyins at the microstakes is good for the less experienced players FAQs like this are geared towards. It is more than they need if they were solid winning players, but they're probably not. So the FAQ already [indirectly] covers your two points, that you need less than 20buyin rolls at the microstakes if you're a solid winning player and that losing players obviously need a buffer as they will inevitibly go broke unless they improve their game.