I didn't mention any stipulations on the downvote, but I certainly think a wide variety could be considered. Reputation or account age could be options, with higher numbers allowing more (or any) downvotes.

" I don't think minnows new to Steemit should be able to downvote a witness, but I hope I'm not being classist here."

I don't really think it's classist, I think you are just (rightly) assuming they are less likely to cast good votes. However, given the natures of dpos, minnows have almost no ability to move the needle on witness votes. I saw a good infographic recently that demonstrated this well, but I don't have a link off-hand.

"trying to read this with friends over,"

The multi-tasking is appreciated!