[legion]

When I'm in that position (the "you" position), I might do either, it depends on several factors:

1) Is there a long line of cars behind you? If so, I might cut in front and try to match your speed as passing.

2) Have you pissed me off previously in my trip? If so, I might cut in front of you and maintain my speed. (Or even rarely slow down if you've been an over-the-top @$$hole.)

3) Do you look like a psycho? If so, I might let you pass and just get behind you.

Of course, being in that position, I don't always notice you closing on me. Yes, I see you when I check my blind spot, but I may not have noticed your behavior prior to this. (There may have been excitement ahead or I was scanning for police.)

But the thing that really pisses me off is when I am in the right lane and come up on someone going slow in the left lane. I will usually pull into the left lane behind them and count to ten and wait for them to pull over. If they don't I pass them on the right.