I have to agree on this one, I really dislike when enarmonically equivalent but extremely uncommon names are used. The key of D# has not one but two double-sharp notes (F## which is actually G, and C## which is actually D). In addition, it includes two more sharps that are enarmonically equivalent to natural notes (E# and B#, equivalent to F and C respectively). It is just an incredibly hard key to reason about.