You can say jerking is useless if you are really good at raring..but RQS isn't. Adding speed to your game is never useless.
Even if your bair combos aren't TRUE combos...9 times out of 10, if you do it right, you're opponent won't be able to airdodge out. I highly doubt anyone else bair combos like I do though. What I do is sh bair with the control stick and A. That way, I'll never accidentally buffer a jump with the cstick. Then, for my second bair, I fast fall with the control stick, and bair with the cstick. If you use A for the second bair, it'll be too hard to fast fall. Right when I hit the ground, I immediately go back to the control stick and A. This is where the true combos come in, since a bair autocancels, you can immediately bair again. I just alternate between these two so it's a chain of bairs that are VERY fast...with no chance of error.
After a bair you can get out a zair. Use airododge + A. If you try to just press Z, you'll airdodge since it's so soon after the bair. I also use the control stick and A for this because you need to buffer the bair asap so you have enough time to get your full zair out...otherwise it'll be short.
Bair -> footstool dair -> dair bounce -> zair -> grab/nair
^like 54% combo everytime
Bair true combos into aerial up B when you do it right. You'll kinda just feel it when it'll work. Don't be afraid lol