Fuse between panels and controller?

Hello. I don't see anything here, on Will's site, or in the book about using a fuse between panels and controller. It's listed as a recommended fuse location on various other sites https://www.renogy.com/blog/how-to-fuse-your-solar-system/ but wondering what you do? Since I'm basing all of my knowledge and education around what I'm learning here and from a Will's book I'm curious as to why this is omitted (and perhaps what else I'm missing. Is it perhaps that the wires are so oversized for the amps coming from panels to controller that it is not a concern?

...answered my own question and corrected myself - but rather than delete I'll post what Will wrote and I had trouble finding:

"...because this blueprint requires so many solar panels in parallel, adding an inline mc4 fuse is very smart to do."

and you can see the 20a fuse he recommends in one of several blueprints https://www.mobile-solarpower.com/simplified-400-watt-fewer-wires-and-alternator-charging.html

Yes what will say is that if you have a group of series of panels in parallel is suggested that each series of panels have a fuse, otherwise, if you have trouble with one series you can affect the one in parallel. If you have your panel just in series no need for a fuse. BUT I have my panels in series and I will put a brake or a disconnector so if you have to work on your MPP you can quickly disconnect your solar input, especially if your panels push 100V or more

I learned something. Did not know that MC4 fuses were available.
Now I am wondering what event or set of circumstances would cause the fuse to blow. Since the fuse would be specified well above the panel’s short circuit current, shorting the cables after the fuse would not do it. The only way current could flow in the opposite direction would be for both diodes to fail shorted. What am I missing?