These older glass tubed fuses can fail and still look good. I think that's why the newer bikes have the auto style "Blade" fuses.
No doubt! The worst thing about that fuse link is that it was a hairline crack. It would be fine when it was cold but, once heated up, the metal would warp just enough to break the connection and kill the bike. After searching for bad wiring or loose connections for about 10-15 minutes (time enough for the fuse link to cool off and regain connection), it'd start back up like there was never an issue.
The link was hidden behind a tiny little panel I never even knew existed. It took me months to figure out what was going on!