Comment by derangedHorse

I think you're too stuck remembering the bad implementations of generality to understand what the original poster is saying. Something like a cache is general and most likely will need to be used in multiple places. If I have a user cache and an application cache, it wouldn't hurt to build both off a general cache. That way I don't have to understand two different cache implementations that are supposed to do the same thing. Now when a new cache implementation is made in a particular domain, there will be no need to review the code that does the caching since developers should already be familiar from working with it in the past. I don't see how it could be "both a source of bugs and an obstacle to reading" unless done improperly.