Theory:Doctor Who television discontinuity and plot holes/The Ribos Operation


 * How can the coordinates of the segment change while the TARDIS is in the vortex (i.e. outside space and time)?
 * Well, it is the Key to Time after all. In any case, if the reading was being taken outside of time all-together, then it would have to read the segment as being at an infinite number of points in time and space throughout its entire existence. To compensate for this, the locator is programmed to lock-on to a given segment relative to a specific timeframe. Once it has done so it will then proceed to track it within that timeframe, so any movements it makes would register even while the TARDIS is in flight.


 * Why do the trained soldiers stop when the Doctor tells them rather than obey the Graff's orders?
 * Possibly due to a mild, mass-effect form of the vocal hypnotic / persuasive ability that Time Lords are known to use on occasion.


 * How can the Doctor walk out of the catacombs after they have been sealed?
 * There is mention of alternate routes out of the catacombs, such as the tunnel the Shrivenzale use for hunting.


 * Exactly how Romana not only ended up in the TARDIS but inserted the tracer receptacle into the control console so quickly is not explained.
 * Both of these events are attributed to the White Guardian's doing.


 * Some of the cliddhagners don't match up with reprise - most obviously episode 2 to 3, where prior to the cliffhanger the soldiers advance for a while, but afterwards the Doctor interjects immedietly and the soliders don't advance. The episode 3-4 cliffhanger is also altered.
 * The White Guardian, in his infinite wisdom, decided to tweak certain events to increase the Doctor and Romana's probability of surviving them. Can't have his fresh recruits dying/regenerating before they've even found the first section.


 * How do planet ratings work? Ribos is mentioned as a level 3 planet - hoping to IMPROVE to a rating of 2 - but it can't do so because many still believe that the planet is flat. Yet previously Earth was stated as level 5 - surely Earth's more advanced than that!
 * * There are several different measurements of planet levels just like there are different measurements of distance and weight. Earth can be a level 5 planet on the Time Lord measurements (which I believe were the ones mentioned previously) and still be a level 2 on the measurements used in this episode.


 * Towards the end of The Invasion of Time, the Doctor's use of the demat gun wiped his memory of recent events. So how come he is able to mention to Romana about wishing he'd thrown the President to the Sontarans?


 * Perhaps the Doctor's memory of what recently happened on Gallifrey was restored when the TARDIS entered the White Guardian's domain.