I somewhat disagree on this. The ability for the government to call a snap election when they are at a high point in opinion polls -- as is happening here -- is a flaw of the British parliamentary system, not a credit to it. It happens in Canada all too often. Sometimes the government gets punished for it (as the Peterson Liberals did in Ontario in 1990), but most often not.

Deciding that her government had the mandate to irrevocably commit the nation to Brexit (the next government has no choice in that, now), but not the mandate to negotiate its terms, is politically-convenient pedantry.