The problem I have with these inferred ‘planets’ is that they all (even the putative gas giants) seem to be in ultra-tight orbits around their primaries. Is that really a stable situation? And if it isn’t - if it’s one that only lasts for a while - how come we’re seeing it so often?
I dunno, but I suspect we’re drawing conclusions from a faulty model.
Clicking through the list on Planet Quest I see most of the planets have tight or very oval orbits. Of course it may be that the big ones or the ones close in are all we can detect right now.