You can dance at the edge of Splodeyville with the .327, too, if that is what floats your boat........
There was nothing dangerous about pushing the .32 Mag to 1500 fps in a strong little gun like a Single Six. The gun magazines tend to be quite conservative in the loads they publish and Skeeter and Dean had a whole article on the various combinations they tried. In my experience, the weak link is the brass. You keep adding more AA #7 and you start splitting case mouths. Sometimes a load that is too hot will flatten primers but usually it is case splits. You back off a bit and you're golden.
I'm sure the .327 can be pushed ever further. Of course, just like a .44 Magnum case compared to a .44 Special case. You've got more room for more slow powder. But IMO, that extra velocity is more than you really need for a woods gun. My normal walking around load uses the Sierra 90 grain JHC bullet at about 90% of max. Runs about 1350 fps out of my 4 5/8ths SS. The max load gets too loud for me to want to shoot it "for fun."
And, like all .32's, it's a happy little gun with mild loads and hard cast bullets. You can load it all the way down to what seem like .22 LR levels.
Hey, I can't convince everybody in the world to like and reload .32 Mag. Or .41 Mag. Or .357 SIG. Or .44 Special for that matter. But I shoot more of those four cartridges than any of my other ones. Even 9mm or .45 ACP. Sometimes it's nice to be a little different!