[Buckeye McFrog]

3.Yield signs at controlled access highways where yielding is optional

That's because our gawdawful terrain around here results in entrance ramps that are too short and/or steeply curved to build up enough speed to join the flow of traffic. So if you are a large slow moving vehicle, it may actually be less disruptive for you to just continue on at cruising speed than to slow down or stop to yield, and then create a huge backup as you try to regain speed. Often times going uphill.

[Vigilanteman]

Maybe, but the place I specifically have in mind as an example is at the junction of US-119 and the PA Turnpike where the clover leaf if fairly well designed and gently sloped. Yeah, it could use longer entrance ramps but the space simply isn't available.

And, no, it isn't less disruptive to continue on at cruising speed and force those wanting to get off at the next exit ramp to suddenly brake and hold up a much larger volume of traffic behind them.

It is nothing more than the "hurray for me and to hell with you" attitude on display.

A typical Pittsburgh attitude, I might add, in a neighboring county where the "courtesy clown" problem is far more prevalent.