I would still rather have the air going into the inlet than trying to go back in through the outlet. Might not be for all, but makes sense to me (aerospace propulsion mech) to keep the turbo rotational speed up and minimize compressor efforts. If you had some kind of anti lag like WRC cars do then probably not an issue as the anti lag would keep the turbo spinning and would counter act the pressure reversion(split second).
On GE F110 engines, we acutally use variable vanes in the compressor to limit compressor loading during starting and certain throttle movements that would slow the motor and cause compressor stalls or surge(air moving towards inlet instead of outlet). This process is similar to a BOV that only opens when pressure is high and you need to "unload" the compressor to keep rotational speed high.
And yes I know A jet engine is a little bit more complicated. But at its basic level it is very similar.
Last edited by roadrash9r; 29th January 2012 at 12:22 AM..