I think that requiring an opponent of a proposal to explain to the proposer how they could improve the proposal is overreaching.
Someone who proposes something needs to make a proposal that is palatable to those who vote. If they have help - great! If they manage to have a good discussion on the forum or wiki so that they arrive at a polished proposal which is universally accepted - great!
But still, it is everyone’s right to oppose a proposal and nobody should be disenfranchised because they cannot, or do not want to, explain their vote. This reminds me of a discussion a long time ago on the forum, where someone said something along the lines of “if you cannot offer something constructive to improve on this idea, please just keep quiet”. But this is wrong. If someone makes a huge proposal about mapping flowerbeds and I am against mapping flowerbeds in the first place, how can I help them improve their proposal? My vote will always be “no”, unless they change their proposal to be “don’t map flowerbeds full stop”. Do I really have to open myself up to a discussion of my innermost thoughts and values (“but why are you against flowers? do you not find them pretty? are you one of those people with a rock garden?”) just to exercise my right to vote? Do I perhaps even have to defend my vote after that, because my reasoning was not stated eloquently enough?
If this idea should come to a vote, I would vote against. I hope that this post is reason enough so that my right to vote won’t be taken away.