Should we encourage the use of screencasts like this one?
If so, what minimum standards should there be for the image alt text and accompanying explanation?
Should we encourage their use
They look cool, and definitely add value, as such. But, I also find them somewhat hard to follow, the screen jumps around a lot, and I can't manually freeze it, or go back a frame. At the same time, I have to pay attention to the keys that are being typed and what it's doing on the screen.
In other words: it's a great supplement, but would not consider an answer with only a screencast to be a good answer most of the time.
In addition, the screencasts won't work very well for visitors with accessibility tools, such as a screen reader or Braille device.
Edit: However, use your judgement. I would say the screencast in the above question is okay (it's not too distracting), the screencasts in this post really overdoes it with the animation, making it annoying & more difficult to read.
No. That's really annoying.
You're talking about a text-based UI in a text-based medium and you want to use pictures? What if I want to copy part of the text? What if I want to search for part of the text? What if I just want to spend these precious few seconds of my temporal existence doing something more productive than waiting for a slow animation to loop around so I can catch the bit I missed while reading actual text?
If you gotta use something like this to demonstrate, I donno, toolbar buttons in gVim or something, then fine. But avoid it whenever possible.
Maybe if they only played when you click them… but imaging having three or four answers, all with one of those. That's a lot of distracting motion on the screen.
In fact, I think that answer is made worse by having it. The video shows a lot of irrelevant stuff which just serves to hide the 'press the right arrow key' answer. There are some things which screencasts are great for showing, but that isn't one of them.
(Not to mention the arrows appearing above the prompt are spaced poorly and have so many funny symbols that they stop looking like things you type and start looking like some weird code.)
There are numerous criticisms of the GIF format in the other answers.
Keeping these in mind, I suggest that a useful screencast format would have the following:
If there were some format capable of these, I would consider screencasts to be a very useful tool.