The chances of the starter overheating a 2AWG cable is next to nil IMO. The components inside the starter are far smaller gauge (maybe 10?) and in the unusual event of a direct intternal short, it would almost certainly open inside long before it overheated a multi-strand cable.
From what I understand most cases of overheating/fires come from poor, hi resistance connections. Putting in a heavy fuse doubles the number of connections. Not a big deal, but those connections are more likely to cause problems in the future than the starter, and as a general wiring philosophy it's better to keep all connections as simple and direct as possible. How many people go around tightening all their cable connections as regular maintenance?