CzechOut wrote: The case you have to make is why these two and not Jayne Kadett. Jackie is entirely irrelevant to this discussion.
No, Jayne is entirely irrelevant to this discussion. I don't even know who that is. That's a whole other discussion, how that companion is treated is entirely irrelevant to this one.
I don't see what the issue is here. They traveled in the TARDIS with the Doctor. They were by his side throughout the whole adventure. They served the role that the companion is supposed to serve. How many trips they went on is entirely irrelevant.
Again, look at how we treat other "companions" for comparrison. Christina de Souza is considered a companion of the Tenth Doctor, and he wouldn't let her travel with him. She's considered one because she went on one trip by accident and it wasn't even in the TARDIS. But two people who went on multiple trips in the TARDIS (Not stories mind you, but trips) with the Eleventh Doctor by both their and his choice (Well, Kinda...) aren't companions? What?
They don't need to have traveled on multiple trips to be considered a companion. That's why we have a "Single-adventure" sub-section.