Grant Erwin writes:

Looks like I-R (like Quincy and the other major manufacturers) don't know
about your special meaning for CFM either.

The statement I was quoting, "Obviously the 10 cfm @1000 psig results in a
much larger SCFM than the 600cfm @ inches of H20." is in error, whoever
said it. The first item respresents 10 cfm of free air, the second 600 cfm
of free air, and the latter is much larger. The meaning of "SCFM" vs
"CFM" has nothing to do with the pressure differences being asserted.