Look Lord_Neomasa, my problem here is that everything you've said/suggested has been said/suggested dozens of times over by dozens of people. Yes, we know Sheik can rack up damage fairly well. Yes, we know Zelda has huge knockback compared to Sheik. Yes, we know that in theory using Sheik to pound on damage and then switching to Zelda to finish would be effective. Some people do this with decent results, but most people believe that the opportunity to ledge guard lost while transforming is just not worth it. Furthermore, many believe that Zelda is perfectly fine at racking up damage on her own.
Once again, this has been discussed to death without anyone bringing something new.
And yes, we do know that as Sheik and trying to recover, transforming to Zelda to use Farore's Wind can sometimes come in handy (depends on your height). But heck, people have been doing that since Melee.
I could understand your desire to create a thread for this specific discussion if you actually had something new to add to it. At this point though, you and everyone else who has posted (including myself) is just reiterating what's been said already in plenty of other threads. Bring something new, and I'll retract everything I've said.