Personally, I find little reason to taste at the very beginning. If it's good I still want to age it for it to become even better. If it's bad I want to wait till it's better...
Do the closures on those carboys allow gasses to escape? If not they might very well pop the bung
Up to a point, Squatchy. I'd be ok tasting them once before they have fully de-gassed and even then only a certain amount of times since there already is quite some headspace. Maybe I'm too strict
I suppose it never hurts to be super cautious. I am not in regards to too much head space. I would prefer not to have any. But I have not found it to be a problem, save for one time. I did have a raspberry mel that browned on me just a little and maybe a sauv/cab pyment. I can't tell yet on the pyment.
I read once on here somewhere that Oskaar had a couple inches of a 6 gallon carboy that had dwindled down to that low over time and he turned it in and won a comp with it. I've made over 200 gallons and only had 1, maybe 2 issues. I can't tell with the pyment just yet. I'm sure your correct that it doesn't hurt to be "strict".
I may be way off base but I feel that this is an issue that has been dragged over from the beer and wine sectors and has very little substantiated base in mead for some reason. I will say I add Things up front in my pyments for color retention. And it also says it's for oxy prevention in red wines as well. I don't use those much. Just depends on what I am doing.
I stabilize everything and the sulfites also do a great job to ward off oxy issues according to the lab coats.
It would be a good idea to try to become stricter so that when I go pro I will have already incorporated these "better practices" as the risk/cost is way more in a commercial setting than messing up a 10 gallon batch.
I have been a "taster" since day one. For me, I think it has made me more aware of the progression of the ferment as well as better able to make additions and have a better sense of timing for the adjuncts as well. I'm pretty good at know that something is headed in the right direction now way before we get there. Rarely do I follow someones recipe any more. And like a chief, I add things along the way as I am tasting the work in progress. It has made me feel pretty confident that even if I make something that isn't quite right I can tweek it to get it right.
Not sure I would have developed those things if I had buried everything as soon as I'm thinking many here (like yourself) do.