While it will work, without being able to calculate CFM I don't see this as being incredibly useful. You could perhaps hook it up and run it at X speed and measure the pressure differential. Then, do some improvements to the house and run the test again and see what the new pressure differential is to get some kind of compairison. But, I'm still not sure how useful that really is.
I did write a blog a while ago on doing your own air pressure test to help find leaks,
DIY Home Air Pressure Test | EcoRenovator.org. The technique works pretty well.