I'm only going to say this once!

So get it through that lump of oatmeal you call a brain...

Its "moot" point not "mute" point. I'm sick and tired of sitting in meetings and listening to people who I think are reasonably intelligent and then they spurt out... (deep voice)..."Well its a mute point anyway." Mute point??? The only thing deaf and dumb in this scenario is your mother because she didn't hear your father sneaking up behind her and couldn't tell him to fuck-off and voila...you!

For those of you who can read and actually give a shit here's the backup....

Moot point is one of those phrases that once had a firm and well-understood meaning, but no longer does. It was just as you say: a matter that was uncertain or undecided, so open to debate.
It comes from the same source as meet and originally had the same meaning. In England in medieval times it referred specifically to an assembly of people, in particular one that had some sort of judicial function, and was often spelled mot or mote. So you find references to the witenagemot (the assembly of the witan, the national council of Anglo-Saxon times), hundred-mote (where a hundred was an Anglo-Saxon administrative area, part of a county or shire), and many others. So something that was mooted was put up for discussion and decision at a meeting—by definition something not yet decided.
The confusion over the meaning of moot point is modern. It is a misunderstanding of another sense of moot for a discussion forum in which hypothetical cases are argued by law students for practice. Since there is no practical outcome of these sessions, and the cases are invented anyway, people seem to have assumed that a moot point means one of no importance. So we’ve seen a curious shift in which the sense of “open to debate” has become “not worth debating”.
The mute spelling is a development that has come about because moot is now a fossil word, usually encountered only in this phrase; there is an understandable tendency to convert the unknown into the known, and mute seems to fit the new meaning rather better. But it’s wrong.