I haven't read the entire thread, so I apologize if someone's already said something similar...
M105 is a strong compound, for sure, but I wouldn't be afraid of a third application. Even a fourth. One thing to remember, is that even though 105 finishes very well, on very soft paints, it'll often times leave marks behind that *look* like RIDS.
Sooooo... here's what I would do.... On an area where you have already done two passes of 105, grab a zero bite foam pad, and do one application of Ultrafina. Now do an IPA wipedown of the area you just used UF on. Then *carefully* inspect the area. You may be surprised out of your socks; you might very well see a completely corrected and glossy surface. Soft paints will often look like they need another application of
m105, when really all they need is one shot of UF to clean up what the 105 left and/or started. Now if this area *does* still look like it needs correction, go after it for one or possibly two more applications of 105, then hit it again with the UF. DON'T FORGET to always follow UF up with a very very thorough IPA or prepsol wipedown. That's the only way to really make sure it's not concealing. I'd almost be willing to bet you'll be at 90%+ correction at this point. Even if you're not, I wouldn't go anymore than four passes of 105 unless I had a PTG. Follow it up with UF, and you should be good to go.
On all the Hondas I've done 105 on, I've been successfully able to follow the 105 with UF. No three-step necessary, but if you want go for the ultimate, you could do another step with FPII.
I love doing Hondas now.... 105 and UF on that paint is one of those rare combinations that allow you to do a two-step to perfection.
Most of the time, an intermediate polish is needed between the 105 and UF, but not on Hondas.
At least, IMHO, YMMV, void where prohibited, for external use only, keep away from flame, etc. etc.
I'm doing a black Acura right now as my final car for the year. I'm using 105 followed by UF, followed by FPII.