Dude, you've got it all wrong.
What makes the code in the kernel so great is not that it goes in perfect, it's that we whittle all code in the treee down over and over again until it reaches it's perfect form.
It is this whittling system that allows us to thrust 25MB of changes into a tree over a week and a half and it all works out. Yes a lot of shit and bugs get added, but we fix and clean them all up, and we do it fast.
So it doesn't matter that the new scatterlist stuff has a crappy set of interfaces, because people like Rusty will fix it up and make it better.