Rm mono

It will print once per *reason* as opposed to once per *variable*.  So in the case above, you are right that it would print twice, but basically that's because I wanted to know all pairwise correlations.  Thus it would say:

Dropping X due to correlation with A
Dropping X due to correlation with B

just to let you know that even if it weren't correlated with A it will still be dropped.  I don't really know which behavior is preferable.  The best output would be:

Dropping variable X due to correlation with A & B