My, my, my, what a fascinating conversation to stumble into!
When I did 1/72 model airplanes, I allowed a scale deviation of 10%, so as to allow some unusual (old) models. In fact, I took it a little further, going closer to 12% to allow for some 1/64 model aircraft.
Also, there was a time here in the States where people modeled 17/64" scale, which works out to a notch over 1/45.
Bowser's old HO gauge Challenger and Big Boy were actually 1/96. Tyco's Ten Wheeler was 1/76.
This isn't even taking into account things like selective compression, "SMILES", what have you.
What brought me back into the hobby was a Kusan battery powered set. A quick measure of the boxcar made it 90% 1/48, or 1/53. Marx is all over the place, of course.
And I have yet to venture into MTH, but they have some mighty tempting items.
Cheers,
Robert
