***** NOT A TEACHER *****
Hello, Mr. Wai:
While you and I are waiting for an answer to your excellent question, I stumbled across some information that may interest you.
He acts as if he knew you.
Imagine your child played truant.
I'd rather we had dinner now.
Four scholars explain that in such sentences, "generally a negative [my emphasis] inference can be drawn."
But they then point out that "I'd rather we had dinner now," the hypothetical past "may express tentative politeness [my emphasis] rather than hypothetical meaning."
James
Source: Quirk, Greenbaum, Leech, and Svartvik, A Comprehensive Grammar of the English Language (1985 edition), page 1011.