Uphill and post jump AI speed

Currently the cross country events are impossible for me on any of the higher difficulty settings. The dirt racing series has some of these issues, but to a much lesser extent. Road based events I run on either Pro or Unbeatable difficulty, but in a cross country event, at these difficulty settings, my observation is that the AI does not get slowed down by either landing from a jump, or by going uphill. Both of these things, obviously, have a major impact on my own speed, so I don’t understand how you’re supposed to be competitive against the AI on these courses.

This is using stock tunes on any valid vehicle for a given championship. It does not matter at all what car I use. I suspect that the added performance score from upgrading all of the drivetrain to tunable components would offset any benefit I would manage to derive from a custom tune on the vehicle.

So the question is, what gives?