The last sentense: the point will sure be reached, and is already reached, in _some_ locations of ASI. Parts of ESS and Beaufort are at the point right now, for example. On the other hand, i doubt your last sentense here relates to Arctic as a whole (please correct me if i'm wrong here), - like, i could hardly imagine _whole_ CAB reaching said point this season.
Therefore, clarification of your statement would be helpful: which exactly parts (= regions) of "ice" in the Arctic you mean when you say that it's unknown whether ice will get so thin that it will simply disappear no matter other influences? A list would be perfect. If possible, of course.
With regards to this year, I mean in so many regions that the minimum record is broken. In general, I mean when the Arctic reaches ice-free conditions for all practical means (below 1 million km2).
The idea is that thickness at some point becomes so low that the influence of traditional factors (like wind, air temperature, insolation, etc) is irrelevant. When that happens across a large enough part of the ice pack, we'll have records, no matter what.
Volume was presumably low after this winter. I don't know if it is low enough for this year to break records no matter what (doesn't look like it though).
I'm not saying anything new here, of course.
Ah, so i was wrong and you indeed meant Blue Arctic event, (practically) whole thing. Thanks for clarification. But then, no, i don't think so; i agree with you that such point exists and Arctic will reach it in observable future, but before it does, i think we'll see Blue Arctic event which will happen _with_ help of the influence of traditional factors.
For the mechanism you talk about, i'm sure Arctic would need yet _much_ higher water temperatures during winter and spring. The thickness i think is required for the mechanism you mean, - "ice so thin it melts summer-time no matter what weather and such are during the melt season", right?, - for that to happen, i'm sure we'd need something like over 70% of total ASI area failing to achieve 1 meter thickness at the annual maximum - more likely even thinner, something like 60...80 centiometers for, again, over 70% of ASI max area.
This opiinion of mine is based on quite very simple consideration: the only big thing which could _both_ thin ASI very much winter-time and spring-time and also practically guarantee Blue Arctic autumn-time, - is big enough and warm enough water currents entering the Arctic as well as big enough and warm enough masses of water in the Arctic seas themselves (after summer-time). Everything else is and will remain much subject to weather. And therefore, if we can "rely" only on enough energy in the Arctic water columns, then to approximate "required" for "Blue Arctic no matter what" annual maximum thickness (most areas) napkin-style, we simply consider that if water is warm enough, in general, to prevent ~half of FYI thickness to form during winter, - then it should be enough energy in the system to practically guarantee summer-time melt of "remaining half" of thickness during summer.
This melting season is yet far from such a "point of guaranteed no return", - if my guesstimate for required thinning is a lucky one. I think it is. And i think that there is probably no other method to quantify here, other than such guesswork, due to shortcomings of existing modelling tech applied to required (here) scale, time period and resolution.