When you’re talking this kind of scale, “client wants to control the edit” is kind of meaningless. Best case, this client will approve or dis-approve YOUR editing choices, and maybe order the excision of whole sections.
When I want to make a pesky client leave me in peace for a good long while, I give them a window dub and leave them to make notes and get back to me. Very often they just stop pestering me and leave the rest of it up to my judgement, because to non-editors, editing, especially screening and logging raw footage and making selects, is deadly DULL and boring work they can’t bear to keep doing for long.
Or they do come back with notes, which is absolutely great, and we’ll run down their list and I can show them I’ve already fixed most or all their punch list, before they could get back to me, and again, this exercise in establishing trust and my ability leads to them telling me to just go ahead on my own, they trust my judgement now.
They can’t micro-manage the edit on this huge scale, nor do they need to. Such a project will die in childbirth, if they try to micro-manage each cut. It’s like Apocolypse Now, where sometimes they only made one cut decision per day.
They HAVE to give you your head to do the rough cut, at the very least, or you should not do the job. Live-switching is a very natural editing process, that gives a good look because it’s a method viewers are very accustomed to. It WILL telescope down the time spent editing by eliminating all the very straightforward edit decisions they ostensibly are paying you to know how to do.
I have spent literally decades doing government training videos, and one thing I have observed is that live presenters don’t always get how different and better doing their spiel as TV can be, in terms of brevity and being succinct. Live presenters are used to a format of “Tell them what you’re going to tell them, then tell them, then tell them what you’ve just told them.” With all that structured laying-out of outlines, the socratic Q and A, the working examples and then the painful long-winded recap and review, there is a LOT of redundancy in just taping any live presentation and calling it “video training”.
It isn’t, really. Not any more than it is “movie-making”, to lock down one wide shot of a stage play for three hours. That’s what they did when movie cameras were first invented, but they didn’t really harness and focus the power of the film MEDIUM until they learned how to move the camera and how to edit. Collapsing time and retaining the essence, while leaving behind the excess noise. What you need to do is leverage the power of the medium, in that same way, and adapt the format to the medium, instead of forcing the medium to simply ape the older format that came before it.
Rolling backups in-camera is your insurance policy against any problems doing the live switch, as you’ve already surmised.
As far as getting “proofs” to the client, I’d suggest a couple of things. Burning to BluRay will get you up to eight hours on a disk, at a very cheap media cost. Don’t even try to say the client lacks a BD player, because you can buy them one for less than seventy-five bucks at Walmart, maybe close to 50 bucks. A BD duplicator, last time I looked, could be had for around two grand.
Pro Res is what I’d edit this on, but H.264 would be acceptable to archive it, IMO (it’s basically what Blu-ray is, anyhow) because h264 is very compact and looks great with little *visible* loss. If you had to set up an FTP server or use a commercial FTP service like YouSend It or DropBox or whatever, h.264 would keep your files smaller. For demos, consider that perhaps the demos don’t need to be the same quality as the HD masters and final dubs. H.264 files of SD wide-screen material, archived onto BluRay, would be VERY space-efficient, yet still good enough to base client decisions on.
RAIDS are so cheap today, and getting cheaper all the time, there’s no excuse not to buy as much as you ever hope to need, and then bill the client for them. You could offer to GIVE them the RAID as a deliverable, or have them buy the RAIDS for you, you use them, then erase and keep them yourself for future projects. Such an investment makes sense to me.
This is just one guy’s opinion, take what you want from it.