Ha good topic, these immediately spring to mind:
- Signs outside Nemesis saying it is the World's most intense ride experience.
- Every "World's steepest coaster" record for beyond vertical drops - vertical is the steepest you can get, going beyond vertical makes it less steep. This was especially bad with Mumbo Jumbo where the "drop" is controlled with brakes. By this logic screaming squirrels have the steepest drops at 180 degrees.
You know, I don't have any problems with these claims and don't see them as dubious in any way.
-Intense can have two meanings; intense as in 'high G force' (ie: something measurable) and intense as in 'full on' (ie: something immeasurable). I've always taken it to mean the latter of those two for Nemesis. And I think it's a reasonable thing to say in terms of marketing spiel, as it is 'full on' (it also helps that it has high G force anyways). It's just a marketing slogan that's not actually claiming anything in my eyes!
-Steepest is an interesting one. I get what you're saying, but equally, "the angle between a horizontal line and the position of the track" is a measurable thing. And I'd say the easiest way to describe that is through steepness.
As for the controlled brakes and Screamin Squirrels: Screamin Squirrels are controlled at all points during their drop (I think?). They're effectively a curved MCBR, not a drop. So you can't really say they have the steepest drop when they don't have a drop. Mumbo Jumbos and El Locos basically just have a trim on their drop; they still 'drop'; it's just slowed down to make it more comfortable.
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I can't think of any dubious claims myself at the moment. I can think of nonsense claims, like 'the world's largest vertical loop' and similar (didn't Fuji-Q go with the ridiculous claim that Do-Dodonpa has the "'vertical loop with the greatest diameter' or something stupid?). Or ridiculously specific claims like 'fastest multi launch LSM roller coaster' and stuff like that. But none of that is actually dubious - they're all right, just silly.