The consensus from the lab folks (people who have kept many for science studies) is that health and being hungry are positively related. In general, I am never sure if overfeeding or an overfed tank (pollution) is inclined to show the reverse.
That being said, there is no standard agreement or quantitative measure of octopus lifespan and food consumption. IME, they won't over eat if fed once a day. When they are full they ignore the food and will leave leftovers to pollute if you fail to find the uneaten remains. Roy (Dr. Caldwell - TONMO Staff Neogonodactylus who has likely the most experience in terms of numbers and years) feeds as much as an octopus will hunt and eat over roughly an hour (Roy correct me here if I misremember) every two to three days for his lab kept animals. The cold water species, in particular, seem to respond well to this kind of regime and was the accepted feeding pattern of the one cold water species I kept (Roy keeps both warm and cold species but not Caribbeans, generally)
With that preamble, I am not sold on skipping days for the warm water Caribbean species. Mine are fed daily with one fast day a week (and sometimes we cheat a little on the fast day with a small treat if the animal is obviously looking for food). Until they are senescent, they are always ready to eat at dinner time (we DO skip a day if they are not hungry). It may well be that the quantity rather than the periodicity is what matters and we may be feeding a common amounts. I see lifespans near the top of the published ranges but not extended.
Additionally, the age of the animal likely comes into play with the optimal schedule. If age at acquisition is a very young juvenile, then the growth rate is exponential at this stage and needs more fuel but in small proportions. As their growth rate slows, the number of feedings may need to be reduced. With little ones we notice that the size of the offering is important and they won't take something too big. My second guessing on this is that waste brings in predators that may find the octopus a good meal or simply take the food away because the octopus can't protect it under its mantle. When they are in their final weeks, often we see old octopuses revert to juvenile feeding quantities and easier to eat foods. Frozen shrimp often comes off the menu. One of my, I wish someone would quantitatively study this, wonder concerns their ability to "chew" or rip the food (ie some kind of failing of the radula - rasping tongue - or buccal muscle controlling the beak).
Soooo my normal feeding recommendation is, experiment
(after about a month in the tank, initial acclimation will not be the same as when adjusted). Start with food about half the size of the mantle (eye size for the very young). If it is fully eaten and the animal is quick to take food the next eay, increase the size by half until you have left overs or a refusal to eat. This will change over the course of the animals lifetime but you will start to observe hunger signs (or reluctance to out right refusal to eat).
Our tanks are not the ocean and our animals are never (and should never) going back to the wild environment so we have to learn how to best keep them in their new world. Hopefully we make trade-offs that are positive by providing a safe environment, regular food and stimulating entertainment but we really don't know the mind of an octopus (or if it has one
).