I think it would be a problem. There are people who cannot wait. If the biggest universe changing event just happened, is 90% of the readership really just going to wait 2 months, or 2 weeks even, or however long the delay is? Nope, they are either going to pay for the digital or pirate it, or at least find out all the spoilers and then have no excitement for the issue. It pretty much breaks the habit.
It also shifts the money off by months, meaning that is two or three or however many more issues committed and done before the first issue even drops or something else happens to affect readership/buying. Marketing also becomes much, much harder.
I am sure if we were honest we could come up with all sorts of other 'problems' that if not industry harming at least would require bigger changes to the way things are done.
Yes and no. Yes, for most stores a lot of titles are not ordered at all except on request, but not all stores are primarily subscription boxes. That is a lot to assume and the possibility that there are a lot of stores that do most of their sales off the shelves should be allowed.
Returnability is big but I think that first line is also a lot to assume. I mean, they will still want them, mostly, if they can afford them -- even a handful of issues. Even if most of the customers plan to buy their pulls, some could take weeks or months to catch up, and in the meantime it makes it difficult for people to even manage their pulls. Usually it is no problem to get something off your pull list about a month ahead, but now I am possibly committed to months worth of comics that I might not even like the first issue I read coming back?So - a lot of business is locked in. And I think people with pull lists will still want their printed copies.
Since publishers are making comics fully refundable going back to mid-March and for at least several months going forward, the risks are mitigated. Stores will be returning unsold copies.
The bigger problem is if the stores can survive long enough for all of this to matter.
Regardless how you feel about the likelihood of any of those issues, it is going to put a giant stress on everyone, from the publishers to the printers to Diamond to the shippers to the stores to the readers.