Yep it's pretty much marketing. They want RO and each of these films to have its own conversation vis-a-vis media and the culture at large. If they ran a teaser before or after for 8 we'd all be talking about that and not RO. It's also starving the market as much as they can - pure anecdote but at RO the other day they played the new Spidey trailer and a guy in front of me said 'They need to stop making these movies.' Not sure if it was Spidey in particular or Marvel in general but it was a weariness that escalated with the Guardians and Logan trailers. You don't want to saturate the market, which they are at one movie per year, so they definitely don't want to create the impression they are. We'll see a trailer at celebration after the RO DVD has dropped, pretty much following the same pattern RO took after TFA.