(These days I don't bother with ballpoints and just use Stretch Needles for all knits and any wovens with lycra. Fewer Needle types to manage)
Me too,
@Morgan , and since I discovered BSK sold the Organ Superstretch HAx1SP chrome coated in packs of 10 I now use those for everything. They last so much longer too!
They're often not shown online for some reason so it helps that they're on the route of a weekly visit to my friend which means I can just pop in and save postage as well.
As for the fabric...I notice this is a lightweight jersey so I suspect all the jersey 'quirks' will be magnified so that anything less than gentle handling and the right needles, stitches etc will be punished. I suspect that's the reason for the warning.
I'd also suggest to stay clear of the lightning stitch and triple straight stitch as they are brutes for anything at all delicate. A small wobble stitch is probably a safer bet.