I kinda get why you'd remove Normal Draft
Blind Pick is a mess if your hidden MMR is low (which it will be since you will move away from that cesspool as soon as you unlock 16 champs).
Mid or feed, pre 30s, random afks and AP J4. You name it.
If all the people who play for practice move to blind pick, maybe the mood will swing. Maybe. If the afks and trolls haven't gotten any reports until now. Maybe matchmaking will be less mismatched. At least that seems statistically likely.
There's also the fact that people will ban new champions and champions that got a VU or a skin. Which is dumb, agreed but could easily have been fixed by preventing bans on such champs (in normals)
I also get that the "ban XX, s/he's OP!" mentality is detrimental, especially during preseason, when Draft Pick is supposed to be a practice mode ... but again, that could just as easily have been fixed by preventing bans for champions with high banrates every other day/hour/game. Or not at all since people like banning assassins.
I get it, doesn't mean I like it. [zombie-nunu-tears]
EDIT: Oh yeah and Draft Mode takes longer.