Sure, but it seems unlikely to be reversible on human timescales, which are the ones that matter to me.

It won't melt on human timescales either. Total mass of Greenland ice = 4e15 tonnes. Upper end of predicted melt rate this century = 4e13 tonnes/century. So it could lose up to 1% of its mass this century or at the same rate, take 10,000 years to completely melt.

Those estimates can always be revised as we learn more, and melting ice sheets are not a linear process - it accelerates both as it melts and as the climate continues to warm.

You're right that it will take a long time, but wrong that we needn't worry. Even just a couple feet of sea level rise will wreak havoc in parts of the world.

We're talking about the irreversibility of the melting here, not the fact that it's melting which everyone already knows and was even happening before AGW started.

No, we were taking about the pace of melting and the impact of that. Don't move the goal posts.