Crocheting a double stitch

Dear users, dear authors,
What is a double stitch?

When crocheting:
Insert the hook into the first stitch, pick up the yarn, insert the hook into the second stitch, pick up the yarn, pick up the yarn again, and pull it through all 3 loops on the hook.
This technique works well for embroidery, since the stitches lie directly one below the other

Sorry, I left out a part—it somehow didn’t make it into the instructions: Insert the hook into the previously crocheted stitch, pull up a loop, insert the hook into the next stitch, pull up a loop, pull up another loop, and then slip all three loops off the hook together. So, essentially, each stitch is crocheted twice.