Well Half-Life games were already one-shots (the stutters while loading new map sections were due to technical restraints, Valves intentions were to make it seamless, and so was the map design), and arguably purer than GoW since the player is in control almost all the time. Since future Halos are likely to remain as FPSs, if Halo tries to do one-shots then I bet Half-Life's style will be the way to go.
Seeing what next-gen hardwares and game engines are up to, I think it's perfectly possible to one-shot even across large spaces (for example riding a Pelican from a planet's surface to space station). However aside from the challenge to prevent such transition procedures from boring the players, an inevitable loss of a one-shot Halo will be the background perspectives. Like, if Infinity's recalling Chief (who's on the ground) in an emergency, traditionally it would be done by switching from Chief's camera to cutscenes depicting the matter (say, a Promethean invasion), then a cutscene showing Chief hop on a Banshee and scrambling off for Infinity, then a cutscene showing Chief crash-landing into Infinity's hangar, then a blackscreen leading to Chief's camera (player perspective) again for gameplay. But if you do this in one-shot, then the invasion can only be shown via radio calls instead of visuals, which loses that urgency, and the flight to Infinity will be pretty hard to design, because it'll stress you out if too long, and will be too funny and unrealistic if too short. And whatever you do, there will simply be no way to show what's going on behind the scenes with Created/UNSC/Banished etc. In fact you can't show anything where Chief isn't present.
Given the already released footages of Infinite, I think it will definitely have cutscenes like previous Halos. However I do believe future entries can be done in one-shot, though it will be a true test of 343i's art and writing capabilites.