the perfect set up would be an electro magnetic roots S/C with a turbo, that would make it much more tunable and streetable.

VW did this with a golf a few years back. made ok power obviously they were being conservative. But figure you use a 60 trim hybrid and 12lbs occurs at 2800 RPM, then they were running the roots controlled by the PCM to spool say 8 lbs of S/C boost til 2800 then the computer would shut down the clutch to the S/C and the turbo would then do its thing.

if you could figure out how to get a reliable clutch system similar to that into the T/K set up then you could be golden.