Yes but it only takes maybe 10 minutes to get past Scappoose and St. Helens and then you're pretty much clear past Trojan and all the way through Rainier and Clatskanie and on to the coast. She couldn't have gone much past Rainier, but she could have made a loop on a long stretch. I've done that. Or even made a grid on open roads with minimal stops. I've done that too.
Cornelius Pass isn't a terribly windy road, nor is it terribly high. We lived in Hillsboro when we first moved here, and my son's best friend was in W. Scapoose, almost to St. Helens. I drove that road several times a week (and others). I'm pretty familiar with it. It's not a terribly grueling drive, nor is it a sharp elevation change at any point. It's pretty gradual up and down, which is less likely to cause pain.
I totally agree. It's not that these roads are so undeveloped nor is it terribly hilly. The biggest thing I have a question about is how she managed to kill 90 minutes DRIVING. I mean, 90 minutes in Portland outside of rush hour is a LOT of mileage.