Electric Vacuum pumps

I have run Power Brakes at 9inches Idle vacuum, sometimes less.
The thing is, as soon as the rpm goes up a bit, the booster is ready to go. Furthermore I am never braking, with the engine at idle, unless I am stopped, lol, so really, idle vacuum is a poor way to measure power-brake performance.
If your engine is pulling against the brakes while stopped, I'll bet you a knickle you have
a lo-stall convertor and/or too much Idle Timing; OR the one-way check-valve on the booster has failed., or the diaphragm is perforated. All of those can be checked and/or changed.