alt Hacker NewsAs an American, I can't see the logic in having the relationship between a proposal (which is an idea that may be embodied in documentation) and a table (which is a thing that we rest our beer upon) as having any importance at all -- regardless of which way it goes.
It seems like plain speech could be used, but this profoundly-irrational jargon was selected instead.
I think in the UK sense 'tabled' is borne out of a pretty literal meaning - based on the proposal literally being brought to the table where the committee are meeting to assess (and potentially vote) on its viability.