Cheers for all the info Badge, although my skill in terms of telling which frame things come out on and such isn't very good yet. I think I can do v1, or maybe it's v2, I'm still not quite sure. I definitely do a grounded magnet, short hop and then do an airborn magnet. Sometimes I can get them really close to the ground so it seems like Lucas is barely short hopping at all, other times my airborn magnets are at a normal sort of short hop height (visibly above ground).
I can only seem to do two in a row normally, using my thumb to alternate between Y and B, but changing to claw grip using index and middle finger I can do however many in a row. The downside to this is that you can't really DJC these and maintain such quick timing. However, recently I've been experimenting mapping L to jump, which means in claw grip you can mash straight from Y to L to B and maintain that fast back-and-forth finger timing, albeit it's not as easy to get the DJC consistent.
There's no real advantage I think to doing DJC claw-grip multimags an awful lot, except as maybe a mixup - I can't really see a situation where you'd need more than a two or a couple. The main advantage I found in mapping L to jump was in doing DJC PKFs (which I'm still not comfortable with the timing for, albeit I can get them occasionally for a while but then use the timing). I can get these using claw grip and double tapping Y, but I'd rather avoid claw grip if possible, so Y, L and side-B inputs feels much more fluid (a similar input to wavedashing).
Also, in another post Badge mentioned
Switching C-Stick to "Attack" instead of "Smash" makes DJC NAirs much easier. This wasn't much talked about here before, because, again, DJC NAirs weren't used that much during 3.0, but with FAir being nerfed and NAir being easier to SDI, DJC NAirs could become more important. At least trying out that controller-setup might be a good idea (has a few other differences to C-Stick set too Smash, notably other aerials requiring more precise inputs and FTilts instead of FSmashes on C-Stick)
I'm having trouble doing the C stick method of this. I can get it sometimes, but the problem is that using tap jump means I accidentally perform an UAir or another aerial. Is this just an issue of me mucking up the timing? Using L to jump can also make DJC NAirs easier, but mucking up the timing (which I'm doing frequently at this point) means performing the NAir at the short hop and also at the double jump, not cancelling it. This might be a good method to attack players at the height that that second jump reaches, but isn't really helpful in a situation where you're going for the DJC but muck it up. And claw-grip NAir is really easy because there's no directional input involved, but again switching to claw grip isn't something I'm too comfortable with atm.