Upon reading this phrase spoken by Sherlock Holmes to Watson:

It would be as well if you could make it convenient not to return before evening.

it made me think about the gradations of speech:
there is an order, a request, advice, and an appeal from Holmes to his closest friend.
One day, I’d love to hear my son say,
“Dad, I’ve invited my girlfriend over to study math together. It would be most agreeable if you could find it convenient not to return before nine o’clock this evening.”