Back in February I wrote about automatic doors and how it was entirely unnecessary to be warned that they are, in fact, automatic.

Basically they move out of your way, requiring no action from you and should only require a warning to those who have A) never seen them and B) have heart problems that can be worsened by seeing such shocking things.

Writers usually have a lot of story ideas, including many “evergreen” topics that can be trotted out whenever they have no pressing items to cover or just don’t feel like doing anything “new.” Sometimes, you sit on a story because you are lazy.

Such is this update.

A month or so ago I had dinner with some family, including my cousin Lauren. She brought up a piece to this automatic door puzzle that had completely escaped my mind: The automatic revolving door.

Now it’s not that I hadn’t experienced one before. The building that houses the post office in Hyattsville, Md., where I used to reside, has exactly such a beast. It’s pretty sweet since most revolving doors are pretty heavy and require a lot of initial force to get them to rotate.

These no-effort doors only move when you trip the sensor, and then only move at one speed (after accelerating up to that speed of course).

That’s where the danger comes in.

With a normal revolving door, you approach with several things in mind. First, you peer through to see if anyone is coming from the opposite side, which would make the door suddenly start spinning out of your control. Second, you know it takes effort to get it going, so you’re hopping into your compartment with a little speed to strike the door with.

When the door moves on its own, both of those become different situations. When someone comes from the other side, the door is going to start moving out of their control as well. That means they will probably wait an extra second or two to judge the speed of the door before picking a compartment to enter. For you, that means adjusting your speed as well since you no longer have to worry about them moving the door too fast or slow for you to get in.

When you do enter, your speed must be different than in the old-fashioned setup. You need only to judge the speed and jump in, then walk fast enough to avoid the back of the door but slow enough that you don’t run into the front.

With so much to consider, it’s no wonder these doors have warnings on all sides letting you know of their automatic nature. Those are truly valuable stickers.

And in case you thought this was the end of my musing on revolving doors–after all, how much more could there possibly be?!–don’t fret. I bring to you also the quasi-automatic door, the ones that open for you once you press a button.

Now these are usually designed for the handicapped, as denoted by the international handicapped symbol on the buttons that one must push in order to engage these doors. But sometimes they are built for the lazy or the guy who just has a lot of stuff in his hands and finds it easier to get into the building that way. To each his own.

This too is another place where I applaud the signs warning you about the door. You may have seen someone in the past walking through without opening it themself and thought it was fully automatic. In such a case you’re probably walking right into that bad Larry, causing at least a few broken bones and probably spilling that double mocha frappuccino you had in your hand.

So seeing the sign, you are then given ample time to make a few adjustments. You can either sidle over to that button–performing the underused hit is with your hip maneuver–or proceed as if it is a normal door.

A further note, sometimes these doors don’t open very easily by hand and thus the warning can allow you to put some more mustard into your pull and not look like a weakling in front of passersby. And I sincerely hope this is the end of this train.