Let's see...
Singles rigs in an overhead environment - AFAIK a bad idea.
Can't see any redundant lights - I always carry one, even in OW, if I need a light to see where I am and where I'm going (like if I'm night diving). That place looks like one where you'd need a light to see that.
Overhead, but no line in sight - AFAIK a bad idea.
Dangling octo - not just poor style, but also a pretty bad idea wherever you may be close to something hard that can snag it.
I haven't seen their certs, but I have a sneaking suspicion that these guys don't have any overhead training.
No, I wouldn't do it like these guys do it. For once, my wife would be mightily pi$$ed off at me if I went and got myself killed that way (and I don't want my wife to be pi$$ed off at me). Besides, I plan to die peacefully in my bed from old age, not from drowning in a place where I have a physical barrier between myself and the big tank o' gas in the sky.
You are diving in a nice place, with crystal clear water, the guide is taking you (and the rest of the group) to see a “a very nice cave” – which usually is a cavern but still! What are you doing? Follow blindly the guide based on the fact that his dive center is doing it all the time and you assume the guy is a “specialist of that area”?
Not just no, but HELL, NO! And I've already pi$$ed off one dive guide by making that quite clear.