> reading and trying to understand source code ... maintaining source code

I think it helps but in general those things are not related very well. For examples guess what this line of code does (this is APL) ?

    X[⍋X+.≠' ';]

According to APL's Wikipedia entry it "sorts a word list stored in matrix X according to word length". It is just 1 line of code so it wins there. But now imagine reading code like that and maintaining it.