[mumblemumble]

Maybe? But, on the other hand, even at 147 characters, your comment seems like a complete and well-composed observation. I don't see how requiring it to be 90% longer would improve it.

I only got past 280 by counting just 185 characters, and deciding to add this sentence as filler.

[clairity]

it's not that you can't have a single, good point fit into a small number of characters, but that good discussion requires more than one good point, and plenty of nuance and thought. it's strictly true that the number limit is arbitrary (and only loosely correlated to 'goodness'), but assuming there is a limit at all, my (simple) point was it should be a minimum rather than a maximum, for better discussion.

[mumblemumble]

Good discussion also benefits from pithy remarks, and suffers from bloviating.

[clairity]

yes, and pithy doesn’t necessarily mean short. =)