Alain,
That just goes to show that "looking good" as judged by you is not a reliable estimate.
Skeptics thought DGT was most likely not for real (like Rossi and others) because claimed technology related to Rossi, and had they been for real very different things - Nobel Prizes, would energy problems solved, etc - would eventuate. In other words, it was not looking good.
Given DGT were not for real, the "public demo" was unlikely to be for real. You can hardly expect skeptics to know how it was not for real until sufficient evidence became available. In fact it was lucky, in this case, that we have that evidence. Also, you can see that adopting a "it must be real unless it can be proven not real" first estimate of these demos is unwise, given the history, and specific circumstances.
You are giving "looking good" and "fraud" as two alternates. I guess correct in this case. But how about the more common one of "hope and delusion" that has afflicted people with eccentric world-saving ideas through history?
The topic here is that it might be better to listen to contrary skeptics like MY, who have been in some cases proven right, rather than ban them. No-one has to agree with her. Indeed I often do not.