I can confirm that this bug exists in Minecraft version 1.8-pre2. I set up a command block to take away the fire resistance effect from the nearest player. The effect is taken away from me but the command block that takes the effect away does not activate the comparator as it should. I know that whenever a command block performs an action, it is supposed to send a signal to the comparator but it does not do that with the fastest clock.
The only way to trigger the comparator is to splash yourself with the splash potion as fast as possible.
I have provided a screenshot of the setup I used.
I can confirm that this bug is in 14w32a
Console spam is also confirmed in 16w04a. I would also like to add that the console spam occurs every time a villager uses a door during the night. I tested them with and without zombies chasing them during the day and night and it only occurs during the nighttime. Hope this helps.