I prefer "hypothesising", in this instance at least. And anyway, I defy you to find a single example of a post where I've expressed a wish to block Brexit, or the like. Obviously I don't speak for all Remainers, but those I do speak to are largely in accord with the idea that, while wishing the result had gone the other way, the matter is settled for the near future and the result has to be honoured.
Wondering if there's a justification for May to [try to] call an early election doesn't undermine this. When I am drawing attention to the possibility of a "no Brexit" party winning, I'm mainly doing so to highlight the absurdities of our democracy that two parts of it could come into direct opposition to each other -- and then the question has to be which gains prevalence? I certainly don't expect it to be anything other than a hypothetical question, but it would be nice if people paid a little more attention to hypothetical flaws in our system and trying to fix these before they actually happen, rather than after.
For that matter, it's generally supposed that Labour as a force is broken in the near future, so it might even be in their interests to *block* an early election to try and protect their seats. Is this really how our democracy should work?
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But anyway. Returning to the topic, Corbyn, when he wins, has a responsibility to try and prepare the Labour party for all eventualities concerning elections. I don't think you need to worry about him threatening Brexit -- quite apart from his low prospects of winning in the first place, word on the street is often that he was in favour of leaving the EU all along, even during the recent campaign. So linking this to an attempt to block Brexit is bizarre, bordering on paranoid. No doubt some high-profile remainers would like to overturn the result, but they are in even more of a minority than Remainers as a whole, so you should stop complaining about it. It's their turn to moan and be ignored, if you like.