I'll edit comments to clarify as long as there are no replies to it, and I'll edit them for grammar / typos after that. Any additions after replies have been added get marked with an 'EDIT' as seems to be common practice here.

English being my second language I just about always find a way to put my foot i my mouth the first time and I don't want to leave a trail of garbage behind :)

Part of the cause of this I suspect is the terribly small input form. If it is an attempt at enforcing brevity then it fails miserably but it certainly serves well to lose the overview of what you are writing.

I'm not sure if 'one size fits all' with this, I like your idea of a history but I suspect that it is computationally quite expensive to do.

Keep in mind that HN does not run off a regular webserver but on 'arc', which keeps just about everything in memory. And that adds up with the volume of traffic that it is receiving.