[William Sommerwerck]

My feelings on all acounts. So the more important question is how
to get the reverb OUT of all these recordings, rather than add more.

Not necessarily. Believe it or not, synthesizing (or extracting)
ambience actually makes the recordings sound _less_ reverberant.

Does this mean that it might be possible to denimbusify recordings
with too much phony added reverb?

OUCH!

That expletive (?) comes from someone who was one of the principal
supporters of Ambisonics in the US.

The excessive reverb (and it is excessive) you hear in Nimbus recordings
isn't phony at all -- its the reverb of the hall in which the recording was
made. It goes away when the recording is played though a UHJ decoder and
four speakers.

I've never experimented to see if the addition of synthetic ambience through
added speakers reduces the effect. It should, but I can't say for sure.