In defense of Martin’s projection of the forces at the Trident: I believe the Royalist army numbers 40,000, which makes a bit of sense if you give that the Crownlands was allowed the time to generate the full mass of their forces (~15,000). Subtract the Dornish force and we’re now down to 25,000, total. I find that to be a relatively believable number for whatever Reacher, Stormlands, and Riverlord contingents were able to join up with the army at the capital, or en route to the Trident.

For the part of the Rebel army, it seems that 35,000 is the given number. The Vale and the Riverlands all had to deal with various infightings, which surely detracted from the available numbers they could bring against Rhaegar. Additionally, after Robert’s defeat at Ashford and his flight into hiding at Stoney Sept, I could reasonably see his Stormlands contribution at the Trident to be negligible. Assuming Ned’s banner calling to have been a rushed affair, I can see 35,000 as being reasonable.

I dunno if I agree with that calculation. The combined total strength of all of these regions is ~90,000 men even without the Stormlands, and I just don’t buy that Robert’s entire army was wiped out at Ashford, given its description as an inconclusive battle. 

So the rebels only mustered a third of their potential strength and yet somehow managed to win the war, let alone subdue the loyalists (who in this scenario had a 2/3 majority?) in their home provinces? I don’t buy that. 

Moreover, Ned had many more months to mobilize than Robb did, when you consider that Gulltown was taken in 282 AC and his army doesn’t show up until 283 AC. But even assuming that he did go fast, that’s still 18,000 men, which would mean that the Vale and the Riverlands contributed only 8.5k each. For comparison, Edmure, after two complete wipeout battles where thousands of Riverlanders were lost and months of occupation by the Lannisters, was able to pull together 11,000 men. 

Honestly, 45,000 would be the minimum number I would find believable, and that’s making some pretty big assumptions about how many loyalists there were and how many men were left behind to garrison the various provinces against them.