Possibly, but when I do downgrade to a different version I never load any of my worlds from a newer version, plus, this has happened once when he left the world without closing Minecraft, then re-entered about 1 minute later with nothing, at first we thought it was a 1.7.2 bug but we created a completely separate world for the snapshot and still had the problem. I have a few other people join the LAN world when its open and they haven't lost any of their stuff (yet), neither have I. I don't see this problem in servers though, when I have hosted a few servers everything was working fine for him and he hasn't lost anything yet.
Possibly, but when I do downgrade to a different version I never load any of my worlds from a newer version, plus, this has happened once when he left the world without closing Minecraft, then re-entered about 1 minute later with nothing, at first we thought it was a 1.7.2 bug but we created a completely separate world for the snapshot and still had the problem. I have a few other people join the LAN world when its open and they haven't lost any of their stuff (yet), neither have I. I don't see this problem in servers though, when I have hosted a few servers everything was working fine for him and he hasn't lost anything yet.