this sums me up until I retired from the workforce, now I avoid high volume traffic, when it does happen I will let them in (unless it is a BMW driver) and maybe make a gesture that they can not see.Close, kill, destroy, scream in rage and generally take years off my life (then do the same as then, when I later found myself in their position).

Are we talking about passing the line in a traffic lane or doing it on the shoulder? On the shoulder they're being pricks, have no problem blocking them.
But too many bungholes don't know how to drive and start merging way before the actual merge point. Use the whole lane until the merge point, that's what it's there for.
we have a road that goes 2 to 1, and I "make an agreement" with the left laners. I pull fully into the right lane and just match speed with one of them in the perfect merge position. They always get it. the asswipes sit back there and fume, and I take it all the way to the point.
If we let them keep flying by it hoses things up for quite a while.
Edit: around here they will write you a ticket for sitting in both lanes.
I let them in because its what i do also 🙂 I see it here on some 2 lane highways where the left lane might go down to one lane ahead and people start lining up like 3 miles out in single file while the cones are like 3 miles ahead. I just go to the cones and merge in 🙂
20 years ago I would have been aggressive and closed the gap and possibly curse them out, but now at 48 I let em cut. We've all been there on the cutting end.