Missing clasp deco stitch
I just wanted to put a bit of a reinforcing stitch on the top of a pocket so I searched through all those hundreds of stitches on the 15000 and I just couldn't find such a stitch. I knew that my 15 year old Janome mc3500 had a very handy dandy asterix, clasp type stitch and was very surprised that the 15000 didn't have it. So I used my 3500 with great satisfaction.
[But we've always done it this way...]
Your 15000 has a Tacking application that can be used for the purpose of reinforcing a pocket. In fact the stitch icon is a pocket and our 15000 video for that application shows it being used on a pocket. This stitch is a lot more secure than the clasp stitch (A01 in the Quilt section, as well as in the Quilting application where it appears on the icon).
The Applications on the 15000 are often overlooked, which is too bad because they have a lot of built-in solutions for many standard sewing problems. When looking for a function it's usually best to start there. I am reminded of a situation years ago when I was working on a project involving stringing wires over a drop ceiling. One worker, appropriately nicknamed "Grog", always stood on a chair to reach the ceiling. The crowning moment was when he actually moved a ladder in order to get to a chair!