Ah huh. Just hype and misleading. I wish that were true and its ability to stitch panoramas didn't fail.
But faced with a very simple skyline to stitch (dark outline of boats, piers, buildings) against a bright sky, both Lr and ACR fail to stitch it up correctly. So either the skyline is too difficult for Lr/ACR or it cannot handle the waves. As it has worked in one instance with long exposures that negate wave movement my conclusion is that waves disrupt its matching algorithm.
If PTGui can match up the shots, why can't Lr/ACR?
I'd criticise other aspects of Merge - how it fails to transfer dust spot corrections to the merged image, the failure to provide searchable metadata more robust than the file name, for instance.
Who knows why PTGui does a better job with some of your pictures? I've thrown at Lr a lot of difficult panoramas, some where I've used a wider lens or overlapped less conservatively than normal, some with buildings, inside and out, trees sticking up and diagonally, waves and clouds. Yes, I have odd ones that disappoint, but Lr's merging performance seems about on par with other apps and roughly in line with expectations. So misleading hype does seem a fair way to describe your statements.