The over-courteous driver, or the later merger?

It is a lazy summer day without a lot of Jalop going on, at least for me. Let's try something a bit different and play a game I would like to call "Which is more annoying?" I have a few of these so perhaps we can turn this into a thing.

THE OVER-COURTEOUS DRIVER
We've all experienced the over-courteous driver; this the driver who stops in the middle of the road because someone it trying to pull out or back out of a driveway or a side street. This is not to be confused with the person who is sitting in traffic and waits before pulling ahead to create a break in the line so someone can get out. I'm talking about the person who stops in the middle of the road to let someone out when they aren't in a long line of traffic, but has someone following them. For the driver behind the OCD, this is an unexpected and potentially panic stop. For the driver on the side street or driveway who is watching traffic, it is an annoyance because that person stopping doesn't mean that someone behind him or coming in the other direction isn't going to stop.

THE LATER MERGER/LINE CUTTER
This is another one I'm sure we've all experienced, though I'm probably more sensitive to it because I deal with it on a daily basis. My commute includes driving on a two-lane connector that splits before exiting onto the eastbound and westbound routes of an interstate. Because of poor highway design, the connector often backs up, particularly in the direction I am going. While most drivers - including myself - get in line and wait for the traffic to chug along, others like to drive up to the split and park in the other lane, blocking the free flow of traffic until someone in the backed up lane to let them in. This exacerbates the traffic backup, leading to further delays.

This is a variation on the late merge for road construction, but adds the annoyance of it being the same place on the same road with the same commuters, every day.

So, the overly courteous driver or the late merger/line cutter; which is more annoying?