That little mud trap behind the rear mud guard..? (D2)

Just looking this monring and I see where the rear arch comes aorund and meets the body where the rear mud guard is, there is a small little "shelf" that has trapped mud and grit on it.

This to me seems like a perfect place for crevice corrosion to start life and cause truble down the line. Has anyone with more miles on the clock than me got an issue with this area at all?

Has anyone doen anything to seal this crevice up or remove the potential future threat?

Or am I just an old lady that smells of wee...!

Cheers

Dave...