I would use them too, although - and I’m saying this being very careful because I don’t wish to hurt your feelings - I’m a lot younger than you judging from your avatar. By the way don’t change it, I like your pink tie, honestly.
But don’t these sentences often cause ambiguity. Or should it become clear from the context whether the sentence is past or present or are the ones I’ve given you always past.
Let me give you another one:
I meet my best friend Michael who’s throwing a party and he desperately wants me to come to it.
I go home and tell my mother: I met Michael just a minute ago and he instisted that I come to his party.
So the party is yet to come, but my meeting with Michael is past.
Naturally, if you write a book in the past, then it’s obvious that those sentences have a past meaning. My feeling is that they are always past, unless you write a sentence like this one:
It’s essential that the children be vaccinated against the swine flu.
Why I would use those sentences, because I like them, I love the English language and though disappearing I still think the present subjunctive is very, very British. I was born in the wrong country and no matter how good your English accent might be, almost that you cannot tell a native apart from a non-native, an Englishman will always know you’re a foreigner, because as Henry Higgins said: Whereas other people are instructed in their native language, English people aren’t. I don’t know whether that is true or not.
Thanks in advance