Theory:Doctor Who television discontinuity and plot holes/The Power of Kroll


 * 'Constellation' is once again used to mean 'solar system'.
 * This is almost more of a "continuity". In the Whoniverse (particularly amongst the Time Lords), the term constellation seems to be frequently used to refer to a star system or group of star systems.


 * The Swampies, primitive in other ways, have perfected the art of bookbinding, since their history comes complete with an inlaid leather cover. (And why keep it in a hole in the ground?)
 * It is possible that before their forced relocation, the Swampies had a more advanced technology or set of skills and crafts which have been lost due to dwindling numbers and other factors. Such cultural erosions have happened to many peoples throughout the the history of the Earth. Likewise, the tome may have been abandoned at the bottom of the well because they have forgotten its significance.


 * The rain pouring through the broken window doesn't make our heroes wet.
 * It falls straight downwards and onto the drying creepers, meaning only their feet get wet.


 * Towards the end of episode 3, the Swampies pursue the Doctor, Romana and Rohm-Dutt. Unknown to the Swampies, Rohm-Dutt is killed by Kroll, however in episode 4 the Swampie leader references pursuing only two escapees, even though he by rights should not be aware that Rohm-Dutt is dead.
 * All it would have taken would have been one Swampie to notice the death and report it to their leader.