score:2
tl;dr: Registration is not required for stays of less than 7 working days
I returned from this trip yesterday, and can report back with at least a partial answer.
My fears that the accommodation we'd booked would not do the foreigner registration procedure turned out to be well-founded. Nevertheless, I wasn't worried by this as I'd been able to clear up the situation for my itinerary when I arrived at the airport:
I was in Russia from Sunday 5th May - Sunday 12th May, making a total of 8 days (or parts thereof). In usual circumstances that would be 5 working days, this particular week included the Victory Day celebrations and was in fact just 3 working days. In any case, I asked about the requirements at the airport on arrival and was informed that registration is mandatory after 7 working days. As I was not in Russia for 7 working days, the details of how long I stayed in one place were not relevant in my case and registration was not required.
It's worth noting that I asked about requirements at the information desk (that is, the answer came from airport staff, not from a passport control agent or other border official) but I can confirm that I experienced no difficulty passing passport control when exiting Russia without having done the registration procedure.
Unfortunately at the time I did not think to ask about rules relating to time in one location when staying in Russia for a longer period, so am unable to clarify whether or not somebody with a similar-but-longer itinerary would avoid the registration requirement.
Upvote:0
A few years ago I was in a similar situation. (German citizen) But the solution was really simple. The receptionist of my hotel was processing the registration and at the end of the day, I had a registration receipt. (3 nights in Moskva) No questions were asked and never I needed it.