After using these a bit I came to the conclusion that they are horrible. I like that they can be used to shrink large pictures, or large bodies of text, but having to highlight the words is a rather crude method.
I've typically only seen 2 types of spoiler tags, ones that basically make the text impossible to read without highlighting it, or the ones that shrink it down to a box, and you have to click to expand it. Doing both methods at the same time is redundant. It is like if it were to say "spoiler warning do you wish to proceed" I say yes, then it says "are you sure you wish to continue"
OK, I've installed a block of French Extra BB Codes...
We shall leave the above one on for now --- [ spoil ] [ /spoil ]
But there is a new one, accessible from the Advanced Editor or by typing [ spoiler ] [ /spoiler ]
There are also a set of other almost completely useless functions in the Advanced Editor.
This includes my installing the optional one for LaTex, and going to the Mimetex site in order to compile mimetex.cgi and then uploading it to the server, despite the fact that no-one here needs it or ever will need it. I'm not obstinate, I just despise inconvenient facts.