Sometimes you ask someone a question and they diplomatically answer, “Well, I would think that…” I want to interrupt and say, “‘Would’? You ‘would‘ think that, if what?” Would is conditional; if you were to do this, then I would do that.
Even worse is “should”–“I should think that…” Should is normative; obligatory. Nobody cares what you should think; say what you do think.
It’s a pretentious Britishism, sort of like saying “he was graduated from Harvard” instead of saying “he graduated from Harvard” or “when I was at university” instead of “when I was in college”.
