I used to be really good at working with big balls of mud.
I actually even started enjoying it at some point - it felt like a mixture between a crossword puzzle and archaeology. There was also something nice about being good at something other people hated that was nonetheless very critical.
Somewhat ironically though, the better I got at it, the class of job I got the better the quality of the code I ended up working with.
Now my mud wrestling skills have atrophied a fair bit.