Tom G. would know but I'm sure he isn't allowed to t
And I'm not being funny about it at all. Can you imagine if all (or at least some) vacuum specs were released? Heads would roll, jobs would be lost, factories shut down because...
The consumer would just look for the best nozzle CFM and throw one in their shopping cart at the grocery store. Remember the great 90's "Cleaning effectiveness per AMP" and rated peak motor HP? Both useless ratings that have fallen by the wayside thankfully.
If you can verify this simple test with your Maytag:
1) vacuum at least 3-4 passes on at least medium pile carpet.
2) Repeat the passes in the exact same spot with the brush roll OFF.
If there is a HUGE difference in forward pushing effort, I believe I have an engineering based answer for you.
Bill