I promised myself I wouldn't get involved with this topic anymore, but, you and no one else knows what they used for criteria when assigning a "rating" originally. I'm sure how much it cost them to build it figured in. How much detail was involved, etc. That said, it would have very quickly lost it's "E" status if no one was lining up to see it. I know that they banter about the use of Letter ratings within the company and even mention it from time to time, just like all of us tend to continue to use a phrase that has long since ceased to exist. Even after all these years, people still call MK... Disney World. That really doesn't change anything. Let's say that a 20 or even a 30 something hears that something is an "E" ticket ride. Do you really think that it means anything to them? If anything they might think that an "A" rating would be the best since that is the sequence of lettering we use for everything else.
Now lets go to the original purpose of the lettering system. When you bought your ticket to enter Disneyland (cause that's where it started) you either bought or were given initially (I'm not sure which) a book of tickets with a counted number of A through E tickets in it. There were fewer E's then anything else because those were the one that Disney projected that people wanted to see. Since it was a limited number and those are the attractions that you wanted, you went back and bought another book of tickets and maybe another and so on. That was based on what they thought you would pay extra to see. It might have been in line with quality, but, it wasn't always. Tell me what is the technical marvel with Small World. None! A bunch of semi- moving dolls, allegedly singing a catchy tune while you rode around in a boat. Big damn whoop! However, it was one that was a must see so it was an "E". It isn't anymore, yet it still has the same quality that gave it that rating before. Why isn't it still an "E"?
Like now, letter rating may have existed, but, there was never a hard manual stating how to rate them, it was based somewhat on what they thought would happen and changed whenever the public reacted a different way by either unexpectedly deciding that it was good, or in many cases the other way around as well.
So, if you don't think that wasn't about making more money, then I have a ocean front plot of land in Arizona that I would like to sell. The same thing applies today, however, there is no additional revenue feed by calling anything an "E" anymore, they just still do because they expect it to do well. If it doesn't they will never mention it again. But, continue to believe that it means anything other then expected popularity if you want, but, there is nothing about it that is important anymore.
Take the 7DMT for example. That was promoted as an "E". They promoted the hell out of that thing. It was going to be the best thing since sliced bread. I believe that they still consider it an "E", however, all our ride quality experts say it is a C or D at best. So, what are they basing it on that the original creators aren't using? All those words to say this, call it what you want, place any random letter you can think of on it, it is still going to be only as good as the majority of guests think it is. They are making that call, not the head office or a few people on a discussion board.
Much to the pleasure of many, I am done with this topic. The horse is dead.