Sorry to interfere with this thread but this question might be helpful to others and maybe the OP as well...
I agree that these Qs go right along with the topic of this thread. Noting that my responses are merely IMO/IME....
Is claying really necessary if the paint feels *generally* smooth?
Short answer: Not IMO.
Longer answer: Opinions will vary, but I'd usually say no. If it's a white/silver vehicle and you have reason to believe that it's contaminated with something ferrous, and you're not gonna do a chemical decon then you'd better at least clay it or use one of the Prep towels. BUT...otherwise I just don't consider claying to be as indispensable as many people here do. Using a Paint Cleaner can also make claying less mandatory IMO. With all my silver vehicles I'd know if regular claying were utterly essential, but that's just my situation.
If one does a chemical decontamination with something like Iron-X and the paint feels smooth for the most part, can one proceed to polishing?
Short answer: yes, if polishing is even needed.
Longer answer: Noting that I use a different brand of different chemical Decontamination products...IMO if you use the chemicals you'll *VERY* rarely also have to clay. I've sometimes clayed while the chemicals are dwelling, but those were special cases with somewhat severe contamination issues.
Used properly, on a not-too-awfully contaminated vehicle, good Decontamination chemicals can do the job just fine all by themselves with no claying IME. And (also IME) they do a much better job than clay.
The reason I'm hesitant to clay is the chance to create scratches...
Even though I'm always saying how I spot-clay without marring the paint..that's just me and my situation. I do agree that most people will cause some marring when they clay, at least if they're not:
1) EXTREMELY careful about it (knead/replace clay after every few inches of contact, virtually zero applied pressure, lots of time..)
2) using very mild clay (which isn't very good at decontamination anyhow), with lots of lube, on not-stupid=soft paint
3) experienced enough to know what they can get away with and what they need to avoid doing
Easy for me to spend other people's money, but a good Decontamination System is:
1) the OEM-tested/approved, way to decontaminate (at least if you use the right stuff; I use ValuGard)
2) the most effective way to get contamination out of the paint's pores and micro-fissures (yeah, even on new paint), note that clay only works "above-surface"
3) basically as easy as doing a series of washes, minimal skill required compared to claying
Of course, plenty of members, including Pros, here do things differently with stellar results, so it's not like I have the one-and-only answer to this one.