In reply to dunnyg:
If someone else has got on a route, especially an ice-route, that's it as far as I'm concerned: it's theirs until they've finished it. I certainly don't want to start up it before they're out of the way and the artillery has stopped
As you say, it's a bit crap to use an abseil to nip in in front of another team. At the very least discourteous. Quite likely to be dangerous too.
There's plenty of ice out there. No need to fight for one route when there are loads of others to play on.
Or at least, there are in Scotland. I've never climbed on Great End. And tales like this don't encourage me to try...