why do hi-end fuses keep blowing, while std don't?

You're missing my point, Mr. Kait. You are in fact making it without realizing it. Listening for the audible effects of a fuse, and evaluating it's electrical behavior, are two very different things. Modjeski approaches hi-fi evaluation first as an ee (as a purely intellectual activity), audiophiles don't.

A point worth making is that Modjeski investigated and reported his findings on only the original Hi Fi Tuning Fuse, not any other boutique brand or design. Each of those has it's own unique characteristics, and should be evaluated separately. The ARC LS16 I bought years ago came with a Hi Fi Tuning Fuse installed, and worked fine. After reading Modjeski's report on their use in his RM-9, I wouldn't dare install one in a power amp tube application (in a DC circuit). Knowing how audiophiles react to criticism of a product they own, I'll bet very, very few have read that report. Suit yourself!

As for RM being an electronic wizard, anyone who can watch his talks at The Burning Amp Festival (and those of Nelson Pass) and not come to the same conclusion is a better man that I. Or better yet, listen to one of his amps! Geoff, I'm going to take a wild guess and say I'll bet you have never heard one. The RM-9, the RM-10, the RM-200, any of his single-ended triode amps, or his OTL's? What amp do you listen to music through?

Modjeski doesn’t talk about the "sound" of fuses, only their electrical behavior. What the internal composition of the fuse does with the gas created when a fuse pops (if my memory serves me well. I haven’t read his Forum posts in in years), what’s it’s "high breaking capacity" (whatever the hell that is. The Hi Fi Tuning Fuse designer didn’t know either, Modjeski reported ;-), how it behaves in a DC circuit (what the power tubes in the RM-9 run on), those kinds of issues.

Yes, Modjeski is skeptical (to put it mildly) of the audible benefits of power cords, fuses, overly-expensive (define that as you wish) interconnects and speaker cables, etc. But one thing you can be sure of, even if you don’t consider him an audiophile: he is an expert at electronics, circuits, tubes, transformers (he winds his own), and, yes, fuses.

There is a great video on You Tube of Nelson Pass and Roger Modjeski giving back-to-back talks to DIY designers at the semi-annual Burning Amp Festival in the Bay Area a couple of years ago. Well worth your time to watch (and learn). Modjeski is now offering a new ESL loudspeaker of his own design and build, and a partnered direct-drive OTL tube amp that eschews the input transformer found in most other ESL designs, as well as, as it's title suggests, an output transformer. I'm dying to hear THAT combination! His little RM-10 amp is THE amp for the old Quad ESL.

At the risk of being flamed, I'll remind everyone of the RM-9 amplifier Roger Modjeski received back at Music Reference after the Hi Fi Tuning Fuses installed by the amp's owner didn't perform their intended task when a power tube in the amp blew. Modjeski went into research mode to investigate the design of the fuses (including speaking to the German designer and manufacturer of the fuses), and reported his findings on his AudioCircle Forum.

I bring this up again only because directly above is the statement "In the long history of audio there has never been a single documented and verified (what's that mean? Modjeski's word isn't good enough?) component damaged by a high end fuse." I have no information of any other than that one instance, but Modjeski explained exactly why the fuse not only DIDN'T perform it's intended task (in it's application in the RM-9's circuit), but why it is INCAPABL:E of doing so (because of it's design and construction).

If one is sincere in desiring to learn what Modjeski has to say on the subject of not just the Hi Fi Tuning Fuse, but all fuses, all you have to do is go to the Music Reference AudioCircle Forum and read all about it.. Or, you can just get defensive, makes no difference to me. ;-)