Well I'm aircraft avionics tech and otto does have a point, but the 747 ACM system runs off about 150 deg 40psi bleed air and has had a heap more money spent on it than any turbo set up we'll ever see. The low pressures, low temps, and low flow rates of a turbo (compaired to an aircraft ACM) all add up to the cooling effect of plumbing back your BOV being nothing.
I'm looking at buying an r32 GT-R sometime soon and I'm thinking about using a trick that the Toyota Celica GT4 had on it called an anti lag valve. Instead of plumbing the air from the BOV back into the compressor side of the turbo I'm going to try directing it into the exhaust manifold on an angle so it gets directed straight at the turbine. This way the turbo should keep spining between gear changes. Now the only problem I can see is that maybe the hot/cold shock of the air on the turbine may cause it to shatter but thats just a minor detail
If anyone can see and huge problems with what i want to do then please speak up. I'm more into electrical stuff so there may be something huge thats gonna throw a spanner in my idea.