Solution to Peter Burrows' detective problem

The answer is that West was able three times to table 7-card support for partner's bid suit! Because we inadvertently changed seats it was actually I who tabled the first dummy, and admittedly the third example is slightly un-real as I had in effect supported partner's suit. But had my partner sat West throughout, as she normally does, she would have put down 7 trumps for me on three boards out of 24! I'm starting to understand why she complains that I always hog "her hands".