I Need To Move A Plant - When Should I Do It?

So many people get very stressed when they need/want to move a plant to a new location. Should it be done in the spring or fall? My only rule of when to move a plant is this:

Move it when you no longer like where it currently resides.

Period.

I move/divide plants all the time, any time of the season, and any time of the day. I move them and have even divided them in full bloom (definitely not the most opportune time to do so). Today I moved a perennial at 2:00 p.m. in 80 degree weather. Why? Well, I was watering and I noticed that the plant did not seem to like where it was planted. It was very small and had no blooms. I had noticed this before, but forgot about it. That is the problem - I WILL forget about it. Today I grabbed the shovel and moved it. There is a secret to moving a plant in the middle of the afternoon on a hot day.

It is WATER, WATER, and more WATER.
This is how I do it and I rarely have any problems.

First I dig the hole (about twice as big as needed to put the plant in). Then I fill the hole with water and let it soak in. Then I fill the hole a second time.