Something of a semantic argument and, I feel, not a correct one. It seems to be predicated on the assumption having been made that a watch was a PMH because it looked similar or in some cases identical.

It's not as straightforward as all that. Some of these watches carry the Heuer model reference, have serial numbers in the Heuer sequence, have Heuer text struck out on casebacks and even sometimes have Heuer text overprinted on the dial. Are we to believe that Heuer would have been happy with their suppliers providing all of this to competitors without involving Heuer at all?

As a debunking it falls well short for me.