As a 25 foot Class C RV driver, I've encountered what you describe from heavy trucks, Class A's, other Class C's, Priuses, and Teslas. It's all over the place. I have to have a certain calm about it, especially on summer weekends on 101/SR2/SR20/etc in Washington.

The thing people don't realize is that speed limit advisory signs (on turns or downhills usually) are essentially mandatory for high CG vehicles - to avoid rollover risk.

To help you understand some reasons to refuse a pullout, here are the conditions that I think must be true for an RV or heavy truck to safely and practically use a pullout: (Maybe I'm missing something)

1) Vehicle is slower than the speed limit or lower than the safety speed advisory by more than 10 mph. (Yes, this is annoying for people that want to exceed the speed limit, but they can use passing lanes.)

2) Pullout must be visibly paved and clear for entry in advance of safe braking distance. (This is often a problem.)

3) The pullout must have good visibility behind it so the vehicle can safely get back up to speed from 0 after stopping. (Sometimes a problem.)

4) Traffic must be light enough such that rejoining the travel lane is feasible in less than a couple minutes. (This is often a problem.)

5) The pullout must have a safe path to return to the travel lane. (I have had to balk pullout attempts after nearing the pullout because this is not always immediately clear at a distance.)

6) Most importantly, the vehicle must not be followed either at an unsafe distance or by someone driving erratically. (I am not going to risk damage to my vehicle by braking for someone following too closely.)

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