[notapenny]

I wouldn't agree they're a bad habit either, but only when used with care. Types like T, and K, V might be as clear to most people as i and j in array operations.

Your example is clear enough because the signature is simple, but in more complex functions I've found that becomes obscure real fast, particularly if types are then passed down to something which also uses generic types. Enabling people to reason about things is not as clear as actually telling them what it is. If the 2nd of 3 generic types is the return type for whatever reason, call it SomethingReturn type and remove that ambiguity.