Dear @kevemaher : As you said almost no manufacturer disclose the the whole measurements process they used including the different standards they used.
Here some examples:
http://www.thevintageknob.org/technics-SP-10MK3.html
http://www.thevintageknob.org/denon-DP-100M.html
On specs this Denon TT is the only that shows Measured spec on speed fluctuations: 0.06%
http://www.thevintageknob.org/micro_seiki-DD-100.html
http://www.thevintageknob.org/yamaha-GT-2000.html
http://www.thevintageknob.org/sony-TTS-8000.html
http://www.thevintageknob.org/sony-TTS-8000.html
http://www.thevintageknob.org/garrard-401.html
Your AS 60db is prety " decent " for a BD design and is really close to the DD MS unit. Btw, @mijostyn my vintage AS TTs never showed that rumble you mentioned is reflected in the subs not only that I do not noted by " eyes " but neither with my fingers against the Denon DP 80 and the Technics SP 10MK2.
I think that the OP really puts the " finger " where it hurts when posted:
"" How low do wow, flutter, and rumble have to be before they become inaudible in a "typical" listening situation? ""
That is in true the real issue for us MUSIC lovers and audiophiles and for what I know I think that no one measured till today with the same standards/process.
I remember that in cartridges the separation spec that normally is measured over the frequency range but manufacturers only gives the measure at 1khz and main reason ( I think all we know it. ) is that at both/near frequency ranges the " figure is way lower over the " figure " showed by the manufacturer that today I think no one gives as in the past when the cartridges came with athe measured diagram of frequency response and separation from 20hz to 20khz and with the test record used, at what temperature, VTF and the like and speed velocity of the diagram.
In those " gold " times audiophiles were way better infortmed to decide what to buy and in those times and talking of cartridge separation specs with severaltests and measures was accepted that the minum separation spec must be 20db with no " difference " if that figure goes to 30db because separation is not linear/flat.
Lyra Atlas Lambda SL shows 35db on that spec but Allaerts Formula 1 is 70db at 100hz and 20khz and " only " 60db at 1khz but neither manufacturer disclose the measurement process about.
R.