So so I'm still waiting for someone to expand the scientific and engineering knowledge base and offer up any advise or theory to help answer the original OPs question.
If the answer is that there is no answer other than trial and error, I'm fine with that. Maybe the mysteries of HiFI tuning fuses will be answered by science someday.
Or even better, if the vendor could provide the answer, that would make it pretty easy for anyone concerned to validate it or not.
Alternatively, there is a lot to be said for the old motto "if it ain't broke, don't fix it". There is always something out there worthy of one's attention at any given time. Fuse direction probably ranks pretty low on teh grand scale of things I would wager, even when one is easily affected by "audiophilia".