Re: Ron knew more than he was telling
The only Dr Who books that I recall seeing, in the period up to Pertwee in "Spearhead from space" (which I think is the story that introduced the idea), were the novelisations of the original TV episodes. Which I did indeed read: by the mid '70's there was a long row of Target books with the distinctive white covers. The earliest of those did take liberties, compared to the broadcast material (e.g. characters - but only the men - actually taking showers and sleeping in the first Daleks story, or climbing on a ladder to reach the lantern on top of the TARDIS, as that was so much quicker than climbing up the inside!).
The real glory years of the Dr Who novels came after "Survival", of course, when we were flooded with New Adventures, Missing Adventures - I'll admit that got a bit much to keep up with: I still haven't finished reading the Timewyrm series! Some of those were meant to be canon, others (hopefully - the planet of the pink poodles?!) not.
There were comic strips, which introduced new story lines and odd facts (e.g. the 1960's - '67, I think, Daleks Album, which gave us Daleks on flying discs - and that Daleks can not see red, so they were in danger of banging into pillar boxes!). Plus stories clearly written for one Doctor then printed with a later Doctor's face drawn in, sometimes even with the costume changed as well!
But if anyone does know of a book that introduced two hearts before the telly, I'd love to know it's name.