There is a small difference, SCO did actually like sue and did have like a coherent theory of trollage.
This troll is simply sending out threatening letters by the ton. What is amazingly stupid about the whole process is that they went after small businesses that are least likely to pay up even if they knowingly infringe and the amount they demanded was far more than most of the targets could pay. Profitable patent trolling usually involves demanding $1 million from F500 sized companies and settling for $50K. Demanding $50K from mom and pop shops is a losing proposition.
This is like the difference between the special and the general theory of IP trolling.
Suing the FTC claiming that the threat of a civil lawsuit violates their fist amendment rights is the sort of action that tends to only lead to court sanctions. The best that could happen is the court combines the actions into one and recognizes MPHJ as the plaintiff which gives certain tactical advantages in controlling time. But the court is not going to do that, they are much more likely to stay the proceedings once the FTC files suit.