In reply to stp:
> It's not dangerous for a belayer to fly up into the air when belaying. It's actually a good thing and perfectly normal, particularly if the belayer is lighter than the climber. By getting pulled up in the air it means the fall is arrested slowly rather than suddenly.
> Without this give in the system there is real danger of injury through a) the shock of stopping suddenly and b) slamming hard into the wall. I know as I've been injured both ways in the past like this.
Yes. We all know. Thank you for reminding us.
> The closeness to other belayers should be irrelevant since the belayer will always get pulled in towards the wall.
Other belayers stand close to the wall to lower/get the rope out of the way for their climbing partner. If someone is being lifted, they have very little control, it's not hard to imagine that they could hit someone else.
I stated the obvious for you there just so you were clear.
> Not sure about the shock loading of the anchor sling either. If the belayer has already been lifted off the ground then most of the shock will have already been absorbed. The anchor slings should be in no danger of breaking and if that's the worry then they should be replaced with something stronger.
Depends on whether it was a fixed ground anchor or a sand bag. Either way, no-one likes their equipment repeatedly/unnecessarily worn out. But this was a little factor which added up to the bigger picture. Don't get sidetracked.
> I would also add a fall close to the ground can be safer than a shorter fall that slams the climber into the wall. But such things are all a matter of personal judgement, and something that comes with experience and practice.
That's beside the point, they were doing fall practice. Why not do it higher up where is definitely safer?