I had a similar feeling with my Independent 1400cfm external blower.

The actual cfm rating will depend on how long the ducting run is and how many turns it takes.

I put up the 15 page instruction manual to the baffle filters on max power and blower sucked the manual right up to the filters. It hangs there indefinetly without my hand supporting it.

I thought there would be more sound and fury but probably a good thing that there is not.

That is the problem, My 1 page also did not get sucked by the blower. that is why I am concerned.
I had the thermador person come and check my installation and he said everything looks fine, but he could not confirm that blower is working to its full potential.

In my small bathroom I have 100 cfm bathroom ventilator. It can suck up 1 page.

That is a definete problem.