All around the intake is room to breathe.
Air does bend around the valve head/satellite some. You can test that on an flow bench by facing a valve till there is no margin left and just an edge...it will flow less than a new valve. That in mind...think if water flowed through 'with pressure' it would fan out and carry somewhat on the chamber across/next to and the cyl wall..the majority/most concentrated will influence near by air too.
Think how a hemi flows so much, think about the valve placement away from the chamber wall. Its rudimentary.
The chamber encroaching sucks UNLESS you can use it as a continuous riverbed, so to speak..to en extent that is. In order to do that..you have to steepen all the seat angles and put the valve down some.
