karstdvr:
free floating stages that are hip clipped or placed on the crotch strap (racoon tailed) do a lot of cave damage. I cringe when I wait for a team exiting the Eye and I see stages banging around like balls on a pool table.
I agree 100% that the cave topography needs to be considered when deciding how best to manage bottles. That was the basis for my comment about taking the cave into account before deciding whether or not to do a setup dive. For a single stage dive, it's a non-issue - just clip the deco bottle as a second stage bottle and you're done. It only starts to get tricky when you have to manage three or more bottles (two stage / one deco and vice versa, or two of each).
I would personally never hip-clip an AL80 in most overhead environments - that's for OW only. For a smaller bottle I might, but it would depend on how low the ceiling was. The Eye entrance is a little low for that sort of thing IMO, and a little more care needs to be taken in situations like that to prevent damage to the cave.
I only use one deco gas (O2) when diving Ginnie, and I will typically hip-clip the O2 bottle until just before I enter the overhead. At that point, I normally unclip and carry it into the cavern zone before placing it. This helps prevent damage to the entrance due to tanks banging around. On the exit, I would normally hand carry the O2 bottle out, and then rearrange everything once I was safely in OW. With a single stage, there's no real need to move the stage bottle to the hip, but with double stages, I would probably move at least one of them (again, once I was in OW) to help reduce the clutter on the chest D-ring.
If you are faced with the prospect of carrying hip clipped bottles through small cave (such as when entering/exiting the Eye), then a short setup dive to place bottles ahead of time might be preferred.
Every situation is going to be a little bit different, so it's difficult to deal in "absolutes". The parameters of the dive plan and any constraints imposed by the environment need to be taken into consideration when choosing the best approach for a given location.