The Doctor-Lite Episode is a subset of The Format-Bender that appears in the show for very practical reasons - they can shoot it at the same time as another story and the Doctor (and/or Companions) who misses most of the episode can devote their time to that or take a few days off. It generally ends up being a Format-Bender as well, because one of the main characters is absent so they do something a bit different.
I split this off from the previous article because it has some obvious effects on the story, and it would factor in to how a game using it might run.
First of all, if you get a bit of advance warning that a particular player will be away for a session or so, you can plan an adventure with the rest of the cast while that one's absent. This could come out like Midnight or Turn Left, filmed back-to-back with the Doctor in the former and Donna in the latter, both of them playing up their isolation, or less darkly, the various specials where the continuing Doctor teams up with a "companion of the week".
Or, equally, you could run a Doctor-Lite Episode while all the players are there.
It wouldn't serve the practical purpose of a Doctor-Lite Episode, but it would let the group take a look at a different side of the setting, and an outside view of their own characters. So this is something like Love And Monsters or Blink, where the Doctor and crew are absent and the story features a new group of protagonists dealing with something involving the travellers indirectly. So the story's still about the Doctor and companions even though they aren't directly involved in most of it. This lets you experiment with the format beyond the absence of the PCs.
Love And Monsters looks at the effect the Doctor and his world has on people beyond his fellow travellers. What kind of mark would the characters in your game leave on the world?
You could crank up the Fear Factor of a new or existing monster that wouldn't be as much of a threat to a crew of time travellers. The Weeping Angels were troublesome for the Doctor and Martha in Blink and latterly the Doctor and Amy, but absolutely terrifying and potentially lethal threats to Sally, Larry, Billy and Kathy.
The practical question is whether to have the normal PCs as PCs or NPCs in the scenes where they appear. Something to decide at the table, and a good reason to keep their appearances to a minimum.
Example: The ? Files
The players take on the roles of a group of Scotland Yard detectives investigating a series of disappearances, stumbling across a conspiracy involving a defunct quango called Torchwood, being stonewalled by representatives from UNIT, all connecting to things the travellers have done... and uncovering something that has yet to happen to them.