Well, you can either have just "perfect" implementations of an obscure language very few people are coding in, or you can also have an implementation of a simil

Well, you can either have just "perfect" implementations of an obscure language very few people are coding in, or you can also have an implementation of a similar language that is imperfect while actually gaining mindshare for both languages. Who's more likely to bother looking at some other version of lisp, someone whose experience is C++, Perl, and Java, or someone who's used Clojure? This isn't the perfect as the enemy of the good so much as the perfect not willing to let the good be its friend.