Ralph - the technique is only effective at High NR and the whole point of stopping the rotor quickly is to avoid blade sail which occurs at low Nr. You are far better off using a normal shutdown technique trying to keep the disc as level as possible with cyclic.
Use the rotor brake a little more aggressively if you need to and shutdown with the wind in the 1 or 11 o'clock (depending on rotor direction of rotation) so any flapback puts the low point offset from the tailboom.
As for using the hangar, it trashes the inside of the hangar and the engineers will hate you for it so you had better have a really good reason to do it. Trying to hide behind a hangar in its lee can make things worse as the wind will gust and the turbulence can give you more bladesail problems than in the open.
In the end, your rotor starting and stopping limits are there for a good reason so going flying when you know it will be out of limits for the shutdown is not so smart.