Cool (New?) Tech:
So I noticed something that I've been doing on the Wii U version but haven't really seen on 3DS. I haven't been able to do it on command yet either, but sometimes when I hit someones shield with a Spin Dash/Charge, it slows down the spinball momentum and I can do a jump that's more akin to a VSDJ as opposed to a SDJ.
It wears down shields more and keeps you in their face instead of flying past them. I've also been able to short hop that VSDJ.
My theory is that it occurs when holding forward from hitting a shield with just a Spin Dash/Charge, then jumping at a certain moment during the multi-hits. People I played against when I explained it to them noticed it as well and said that it caused a lot more hits to their shield than normal. It's sorta like that thing Wizzy would do with Sonic in PM.
It's Thanksgiving so I probably won't be researching this for a bit yet, but wanted to share before I forgot.
Happy holidays!