It's not that simple, they take the mined coins pay out in BC but then use the profits from said mined coins to then buy up BC on the markets. It's a multistage process, basically it creates constant buy support. Here is a normal day for blackcoin on Mintpal
24 Hour Volume:
364.171 BTC
This is 80% of the BC multipool buying up blackcoin to sustain and drive it's price. If you watch it daily you'll see the btc volume is always ridiculous because of it. They then take the BC purchased and distribute it like a cycle of events to the ones mining their multipool.
I think it's a great idea, wish I knew something about coding because I would support this with my rig.
I don't think it's life support for a dying coin but it is in essence life support. Unless im misunderstanding the concept the part that gets me is that it centralizes the currency. Without that pool and the operators the coin likely dies. One select group controls the fate of the coin no matter how many followers there are. The coin relies on the group to profit from mining alts to boost there own coin value. It centralizes the risk/reward.