I just realized that this is silly for Pikachu. >.>; Since Pikachu can DJ out of a QAC (easily, might I add), that means you can easily do a SJR... than ISJR... than QAC when you choose...
...
...Sillyness. Not to mention the aerial lengths and double jump height is near perfect for this. The timing has a short enough gap to not be too hard, but also enough time to decide if you want to air dodge, QAC, or attack. In other words, sillyness. Sure, you could always do an aerial, land, than QAC out of that, but this works well too. SILLYNESS I TELL YOU!
...So yeah. Another use for SJR/ISJR is making Pikachu SLIGHTLY more mobile and silly than Pikachu already is. ...Why do I get the strange feeling that Pikachu may be used more in tourneys in a year or two, and not be as much of a niche character as Pikachu was in Melee? XP Well, the funness of this all with Pikachu is enough to make me switch mains. It's just... fun. >.>;