I was looking for something to explain the two dots slightly forward of halfway back on the mantle that seem to be common for most octopuses. Carol noticed them in one of the hummelinckis so I went picture shopping to see if they showed up in other species. What I found is that they seem to be present in all or most of the octopuses in Norman's Cephalopods A World Guide as well as in many photos I looked at on the internet. One diagram I found placed the forward set of poison glands (I did not know they had two pairs) at about the right place so I was hoping the paper would mention the spots. It doesn't but was worth posting.
From this paper and many others describing various surgical insults, the animals appear to be amazingly resilient. Hack off significant parts of their anatomy, slice them open and remove or sever parts of their brains, and they are generally back to hunting and feeding in a day, sometimes in hours.
I took advantage of this in my story, as you know.
And yet chemically they can be sensitive indeed. It's an interesting combination. A creature whose life is so very ephemeral for its level of brain development, and yet it possesses regenerative and healing powers that would do a mammal with a century lifespan proud.
With eight arms and so many "spares" available, it's surprising that evolution selected for a substantial investment in regrowing a lost and usually redundant limb.
The removing the jelly part made me a bit squeamish as it seemed they did not know what they were removing.
You have to keep in mind that these animals were only kept alive for a few days. I suspect they would not have lived much longer with the alterations. If nothing else, infection would have become a major issue.
The regeneration gene is certainly an interesting one and it appears we carry it as well but it is turned off. Why a short lived critter retains it and long lived ones don't seems counter to natural selection. Perhaps it is the ability to protect and prevent amputation that turns it off.