Part of the problem here is a concept sometimes called
hypercorrection.
When people speak and try to be grammatically correct, they go with what their gut tells them is the correct way of putting it. Ironically, their imperfect understanding of the "rules" of the language result in them
hypercorrecting a construction and actually taking it from a "correct" form to an "incorrect" form. The following are examples are hpercorrections that are actually incorrect:
- Give the book to whomever opens the door. (Should be whoever)
- Whom did you say was calling? (Should be who.)
- When you are done, please return it to Joe and I. (Should be me.)
Because of its linguistic origins, "dived" is indeed correct, but how many people know its linguistic origins? As people have noted, it sounds like a series of verbs whose linguistic origins are different, so hyper correction leads to the use of "dove." It is not until you ask them to take it to the next step ("I have diven") that they see the problem.
Personally, I'm OK with it. As others have noted, language is a fluid medium, and it changes constantly. IMO, most of the change is for the better. English is a conglomerate of many other languages, and this process helps even things out and make it simpler.
If you want to be truly bored, I can treat you to an analysis of a grammatical "error" committed by probably 80% of the English speaking world every day. It takes many, many hours of English instruction to try to teach this error in school, with little effect. IMO, the "error" is not an error--it is a natural evolution of the language resulting in a very simple new "rule" in the English language that is superior to the old one. We ought to leave it alone.
BTW, the rules of the English language were first created in the 18th century by a Latin scholar. Many of the "rules" of English were created by him because that is the way Latin worked. Chaucer, Shakespeare, Milton, Dryden,--somehow they managed to speak English without knowing any of the rules of English grammar.