I was the OP. Thanks for all the advice. I only made it to Hyder (scheduling issues back in real life). The roads were all paved except for some construction areas, some turn-outs/rest stops and some gas station parking lots.
Before I left, I practiced on some gravel roads by my house. The BC/Hyder gravel didn't present any problem at all. The gravel used in BC is a lot different than the gravel we have in Eastern Nebraska or stuff I've run into in the mountain states. It's smaller, flatter and it compresses a lot more so riding on it didn't seem much different than riding on chip seal county road.
The one big pucker point for me was a construction zone North of Osoyoos on BC 97. There was construction on both sides of the road (not on the road itself). Dirt trucks were crossing the road and had dumped a layer of dirt on the asphalt road surface. In order to do everyone a "big favor", the construction company watered a 1,000 foot section of road to keep the dust down. They didn't blast the dirt off, they just got it wet. Instead of dirt, it was snot slick gook on top of the asphalt.
I followed the advice here, stood on the pegs, looked far down the road and kept going. No problems, but when I started into it, it was an was definitely an "Oh Shxx !!!" moment.
I've spent my life riding first BMX bikes, and then mountain bikes when I was in high school and college and ever since.
Riding in the dirt on my RTP seems perfectly natural to me as I've spent most of my life riding two wheeled vehicles off-road. The only problem with taking the RTP off-road is that there are a lot of nooks and crannies to clean after-wards. Standing up on the pegs, not looking at the front tire/ground immediately in front of the bike, and relying on the rear brake instead of the front brake are all perfectly natural actions for me when riding the RTP off-road.
IMHO, the only difference between a RT and a GS is the plastic wrapper and the tires.