A pre-wet is advised to temper the drum and film to 100 F. It causes no problem and helps a lot. I have run lots of film this way for over 20 years. It works.
Retained silver in the film causes muddy color in prints, higher grain, blocked highlights, and sometimes crossover. Retained or excess silver in the chemistry causes retained silver in the film so it causes the same problem in the end.
Remember that you can have retained silver metal and retained silver halide depending on where the silver retention problem takes place. The retained silver halide will gradually darken causing dmin to go up and shadows to become compressed with odd color crossovers. The retained silver metal is mostly retained in dark areas in the negatives which cause the highlights to become compressed and odd color crossovers. Grain can go up at either end depending on the type of retention.