You've pretty much got it down. It's pretty simple, yet diverse as to how you can use it. There's so many situations you could use it in, but I'm going to let you figure those out on your own. Just remember a few things about the technique so you don't get caught doing anything bad with it:
- It only creates a single block, any other blocks to get out of a large-scale technique would require more applications of the technique.
- Once you've used it for the intended purpose, it disperses. It's not really a long-lasting technique or anything.
- I should mention the size also isn't that big, maybe 30cm cubed, so about as big as a small fishbowl.
And that's that, the technique is yours.