Well, I can’t say that I have done the suggested extensive experimentation (fuse one way, then the other way, then back again and again, then at different rotations, etc), nor do I plan to, but I was monkeying around this morning behind my equipment and knocked against the power cord feeding my ModWright 9.9 power supply, thus blowing the SR Black fuse inside. The fuse did its job. UL would be proud.
Not having another Black fuse of the proper rating/size on hand, I installed the stock fuse that came with the MW to get the system back up.
The soundstage collapsed like the Hindenburg; width, and especially depth, just went "poof". Not subtle at all. The sound with the stock fuse is not bad (yet different), but my world just became relatively two-dimensional and unacceptably smaller in proportion and space .
That’s my tale, now the FoS crowd (not you Al) can fire away about my sanity issues, lack of education, gullibility, etc. or how my equipment is crap (you out there Shadorne?).
Dave