I don't think it's a corner case. I know of many software PVR's that support this. It just makes sense IMO. Why use another tuner to record a channel that's already being recorded?
Perhaps you should explain what you are looking for in more detail, because I'm not sure I fully understand.
I
think what you are talking about is the idea that if a tuner is in-use on a particular channel, that it should "prefer" to record other shows on that same channel later that day using the same tuner (to avoid a set of tuners "ping-ponging" back and forth with a bunch of consecutive shows in one night).
This
can be useful. I've used PVR software both before and since the ones I used had this feature (both BeyondTV and SageTV do this). Sometimes the "ping pong" can be problematic. This happens most often when you have "handles" on your video files (start recording 2 min before, stop 3 min after). The handles are useful if you have shows that don't always fit their assigned schedules quite perfectly, to avoid missing a scene here or there (nothing is more irritating than when you miss 1/2 of the, usually hysterical, "bonus" clip at the end of BBT). However, if you subscribe to a bunch of shows that all air sequentially, you can sometimes run out of tuners (or unnecessarily degrade to a lower quality analog SD tuner, perhaps) not because a tuner wasn't free for that 30 minutes, but because it wasn't "free" for 4 minutes of that 34 minutes because of the "handles". This avoids that problem. If shows air sequentially, the tuner will ignore the relevant conflicting handles and keep recording the channel. It isn't always perfect, though and sometimes can work against you. The logic can be tricky.
So, anyway... I'm not sure that is what you are talking about. Because you might be talking about recording multiple
simultaneous things (two different audio tracks, maybe) on the same tuner. That, I have to agree with Matt, is probably a bit of an edge case. Might be cool, but... Not a top-tier required feature for most users, I'd guess. I think we're still in "get the basics up to par" mode with MC's PVR functionality.
However... One thing I feel is lacking in this system from most of the PVR software I've tried is maintaining the connection to that "stream" of programming after the arbitrary "cut" points.
So, in my setup when Sage encounters a day where a bunch of shows air sequentially on the same channel, it will usually record them all on the same tuner (it doesn't
always seem to work, for whatever reason). It is nice, even if it does "cut" one of those scenes, the division is almost frame-perfect. I think it must keep the recording going seamlessly, and then "blade" the file afterwards to make the cut. If you can find the next "piece" of the recording, you can pick back up
right where you left off, usually in the same "word" of a line of dialog. But
finding it is often the problem. If, despite my handles, a show still ends abruptly mid-scene (like one of those bonus scenes I was talking about before), and MC
has the next "piece" in-order, it would be nice to have it just seamlessly continue into the next file until I hit stop. Or at least queue the next file, and lead me to it in some way.
I've often "subscribed" to a particular show two or three years ago, or based on a search. I don't know
when they're scheduled, more than a vague "this show airs on Wednesday, I think", for all but my absolute favorites. And I certainly don't notice if they move the schedules around, or new shows start airing and suddenly things conflict or whatever, unless it tells me. But figuring out what show that "missing handle" is on is often quite challenging.... Involving finding the particular show I was watching in the guide (many days off, usually), figuring out what aired after it, then figuring out if I have that show recorded, hoping it recorded that airing of the episode and not some other airing, and then checking the beginning of that file for my missing scene. Usually by then, I've lost interest, and my wife
certainly has.
That would be a very helpful and unique feature.