Well, sorry I shouldn't have said that. You guys both bring a lot of good knowledge. It's just that one of you is obviously Irrippi Ontor and the other Lhankor Mhy and you always disagree and when that happens it seldom stays on topic.
Let's get back to the topic: Obviously there is enough proof that yes, barding IS a thing in RQG. What can we infer then about its cost and weight and now that we know there is a STR and SIZ limit for carrying heavily armored riders, how much should barding add to the minimum stats necessary to carry an armored rider AND wear barding?
How many "things" is barding? Well, first off, I'm guessing the SIZE of the rider is added to his "things" and this must be the what forms the basis of the average size and Str of the horse that's needed to carry a rider. I"m basing this on a warhorse needing an average STR and SIZ of 26. Average human size is 13. Average armor "things" for plate armor is 11 and with leather under and quilted 13. Total 26. So how many 'things' does each piece of armor contribute to a horse? I would guess the same as it does to a human. For a human, carrying the horses armor would be really hard, but it's meant to spread the weight around a horse so plate shin guards would be 2 "things" for hind legs and two "things" for forelegs and so forth. These "things" then increase the necessary average STR and SIZE needed for the warhorse.
How much does it cost? An average horse is about twice the size of an average human. So a quick off the cuff estimate is twice the cost of the equivalent human armor. However, I could - and just did - whip out my RQ 3 books and compare barding to human armor. Doing so, I see it varies but a simple rule of thumb would be that a horses armor cost 50% more than human armor of the same type.
So I guess I unofficially answered my own question.
That is, unless someone spots the answer somewhere in the new rules and I just missed it.
Thanks for playing Pin the Breastplate on the Goldeneye.