Not necessarily directed at you, but this line of thinking seems kind of ridiculous to me.
You are now maintaining that the guy who went to Afghanistan and actively participated in the conduct of military operations in a tactical/hostile environment is less "tactical[ly] proficient in his community" than the guy who stayed home and simply trained to conduct military operations in a tactical/hostile environment?
Yes.
In Marine aviation, if you leave a flying squadron (especially as a JO) for a non-flying IA billet, there's a reason for it. And, even if things are hunky-dory and you just want to expand your horizons, the assumption will be that you got booted from your squadron for a definite reason. If you don't believe me, go away from the skid community for a year-long non-FAC IA at this point in your career and let me know how it works out for you.
You will be at least year behind your peers with hours, quals, MOS credibility, etc. When you come back, the squadron you go to (which probably won't be the one you left) will now have to find time in their already limited "white space" (thanks to increasingly suffocating administrative requirements) to refresh your quals. In the meantime, your buddies have come back from a skid deployment, are moving up the chain in the squadron, working on advancing their quals, going to Yuma, going on FAC tours, etc.
At some point, you'll all be competing for orders. In our line of work, a multiple-deployment WTI is going to have a much easier time finding a job than a guy who did a deployment as a nugget then went on a BTT/MTT/whatever they call them this week and is now working on Section Lead. And "Oh, By The Way" (another MAWTS-ism) at some point you're going to be competing for promotion. Again, who is more marketable for the long-term health of his community and the service: The guy who has stayed in his MOS (save for a FAC or PME) and worked his way up to a point where any squadron would love to have him, or the guy who essentially took a year off from flying - albeit to do (so-called) important work - and is now playing catch-up at a time when he "has" to come out of the cockpit?
I know where you're coming from with guys being 'in the shit' vice being CONUS and doing whatever BS frag SOTG has dreamed up this week, but I've seen this story play out numerous times in the past decade...and in the vast, vast majority of cases, the IA has not even come
close to being 'netural' for the affected Marines.