Did several searches on FT but didn't come up with anything, so posing the question:

Is it generally OK to check in additional luggage at a layover in the middle of an itinerary?

The situation is I'm planning a vacation to Asia or Pacific in June, and many itineraries return via HNL. I have some stuff that my sister's family is storing for me there, and on the way back I'd like my sister to drop off one or two boxes at the airport during the long layover and I'd check them in. As during vacation my wife and I travel light, we'll only be checking one bag each outbound, so we wouldn't be exceeding normal check-in allowances even with the additional baggage.

I'd think it'd be OK, sometimes the carriers force you to check in (at the counter, not gate-check) a carry-on in the middle of an itinerary anyway. So why shouldn't you be able to choose the same?