Do 45 rpm 12" LPs really sound better than 33 rpm?

I should disclose first that making a 12" at 45 rpm takes the LP feature away, which I don't care for.  More importantly, all else equal the faster the speed the more noise will be generated.  This can be significant for the stylus tracing the record groove.  Everything is a trade off.  Some of the gains are offset by the loss due to the inferior signal to noise ratio.  The extra vinyl muffin costs pennies and it is actually easier to master at the higher speed so it takes less studio time in most cases.  Time is money.  On balance it is a marketing ploy to pry more money out of the consumer for a more profitable product.  Sometimes 45 rpm records sound better, but not always. 

Sometimes yes, sometimes no. So many factors go into it. 

I have mfsl pressings of the Jefferson Airplane’s Crown of Creation at 33 rpm and Volunteers at 45 rpm. Both originally mastered by the same guy, Wally Heider. 

The mfsl at 33 sounds decidedly better than my original press. The mfsl at 45 is at best a wash. 

Differences that favor the original 33 version over the re-issue 45 version could of course be related simply to the quality level of the respective manufacturing processes.  Those are variables we cannot control for, and the data are worthless for saying that 33 is superior to 45, as a general conclusion. Bill, can you amplify on your assertion that "the faster the speed, the more noise will be generated".  What kind of noise are you talking about, for one thing?  Are there some published data that support your contention?

Compare a 50-60's 33RPM album to a reissue 45.
I likely will hear the period press as more convincing. Typically any reissue-33 or 45 is a let down,IMO.

 Now, if that period album ALSO were pressed as a 45, that may be noticeable.
I'm  not aware  of a period 45 Kinda Blue or Time Out.

I have the 45 of Ella Fitzgerald's "Clap Hands, Here Comes Charlie!"
It sounds perfect like a CD. 

The 33rpm period mono, (1961) is more engaging. 

The discussion is degenerating into a series of inconclusive anecdotes. If you take the single master tape from a modern studio and from it create both a 33 and a 45, on the same lathe using the same source of vinyl on the same day and then play the two versions on the same turntable with same tonearm and cartridge, the physics say the 45 will sound “better”. In any single instance, for many reasons unrelated to rpm, the result can be otherwise. Period.