In reply to DaveHK:
> (In reply to masa-alpin)
> [...]
> That's not really how it works. The first things to get stripped and be out of nick in a thaw are buttress routes. Ice routes actually persist for a lot longer. Obviously in an extreme thaw collapse is an issue.
Well, when a route holds enough ice, that doesn't mean it's good to climb, does it? In the temperature above zero, collapse is a possibility as you've pointed out, and placements, particularly when climbing slowly, let alone screws, are less trustable... I don't fancy that.
I agree buttress routes that critically rely on what little ice they hold are proner to thaw than many ice routes. But if not, and if turf-independent, they will be still climbable under thaw (though whether you can claim a winter ascent is debatable). That's what I think.