But isn't this the same as sending the block to die?  It's like "Yes we heard that you want toonami back, here it is... at 12... where it won't get a new audience and will barely be watched because everyone who grew up with it stream their shows now or are sleeping"  They need to bring it back after school to gain a new audience.  And then feed the new audience to Adult Swim.  I think that's the real reason Toonami and Adult Swim worked so well.  Toonami was Adult Swim's feeder block, get them young, and when they're older keep them at night.

They figure it will optimize what is otherwise the dead air (viewer-ship-wise) of Saturday late-night. They're not sending it out to die, they're putting it in the only place that they can't capitalize otherwise, keeping it alive but obscure. Motivate the anime fandom and at least you get someone watching at that timeslot, but you're not interfering with the higher-rated timeslots.

ahhh....good memories!!! they need to bring back G-Gundam!!! BURNING FINGER!!!!

In a way you're right, but they're trying to get people who used to watch Toonami to watch and that's a big gamble.  Part of the problem Toonami faced was that it was moved to such a bad timeslot.  Though I personally question if Cartoon Network still gets the same viewership after school the way Toonami used to bring in.  I mean just looking at the current line up, there isn't anything enticing to bring up viewership.  I mean it couldn't hurt to put in some action shows between 3-6 regardless of it being anime or not.  Hell even 6-9 wouldn't even be that bad for some action.