The role of the apostrophe

If I have to proofread a paper again that uses apostrophes in plurals I think I'll scream. These papers are by highly educated types who have English as their first language. Let me summarise: apostrophes are for possesives (Dud's Occasional) or contractions (can't, won't, don't etc). And that's all! Even when pluralising acronyms, apostrophes are OUT. CDs, DVDs and TLAs are not excuses to break the rule.