> > Under what circumstances would you possibly be able to exclude it?
> When I have run the test games with an engine that does take full account of the mating potential or lack thereof.
And how will you know that there isn't some other potential flaw that you haven't thought of? Presumably a less thoughtful person in your position could have failed to consider the issue you are now addressing, and would therefore already be just as convinced as you expect to be after your next test. Should we dismiss a bunch of experts that have made no mistake you can point out simply because we also can't point out a mistake that your engine has made when it gives a different result?
Alternately: there are significant differences between the ways humans and computers play chess, so theoretically some pieces could have a different effective value in human vs. human games than in computer vs. computer. I don't see any particular reason that Commoner should be such a piece. But if it were, a bunch of human experts agreeing on one value and computer tests reporting a different value is pretty much what we would expect to see, right?