1. Re Ron's examples, some would say the Present Perfect is NOT ok for both Q & A: Did you eat lunch in the afternoon/at three? Did you visit Dalian in July? and not: Have you eaten lunch in the afternoon?....etc

2. ON THE OTHER HAND, there can be a real meaningful difference between the Simple Past and the Present Perfect, depending on the intended message or context.
Mother to son:
Did you do your homework?
Son:I did (Give me a five! She didn't ask and I didn't say I'd finished it!)
Mum: Have you done your homework? (Completed it?)
Son: Um... (start minor defensive tactics) the neighbour's cat was having kittens and I'd to get the vet but Uncle Ron took my mobile (new age kid) to ask aunt Julia over for dinner but Mary said she couldn't....(then major diversionary tactics) aunt Mary'd been kind of mean to Liz (Uncle Ron's wife) 'cause I'd heard her say last Thanksgiving that Liz's turkey was from the Thanksgiving before that (mum's eyes open wide)...and yeah mum (easing into counter-attacking mode), you still owe me that dollar for doing up my homework last week... (with betrayed but forgiving glance) I've to run, mum, the neighbour's cat's still having......

3. In Singapore, kids (on the streets, in the malls) struggle with the Present Perfect, choosing (subconsciously) to use it randomly in place of the Simple Past, because (I think) they gravitate to this unfathomable city slicker to know it better, compared to plain country cousin the Simple Past.

4. Also, I think adults tend to ask questions to kids in the PP (as wives do to husbands) and the knee-jerk reply is also in the PP, because the message is "have you done it", not a straight-forward "did you do it". The latter allows an escape route because it doesn't address COMPLETION.

5. My conclusion (IMHO) is that there are contexts where there is no, or hardly any, difference between the two tenses, and others where the difference is intentional (conscious or otherwise).

Trying to be light-hearted in our exchanges, like Ron.