I'm a Navy Derm resident. I have rotated at the military derm residency programs at NCC (Army and Navy combined residency in Wash DC) and San Diego (Navy only), but not SAUSEC (Army and Air Force combined residency in San Antonio). From what I've seen, I believe Military Derm programs see the same type of Derm patients as Civilian Derm programs. You occassionally see an interesting patient here and there, but you mostly see bread and butter stuff (ie, AK's, skin cancer screenings, warts, eczema, psoriasis, etc). HIV and ID Derm (other than Leish) are NOT seen everyday, NOT every week. There's just not many HIV patients in the military patient population. Also preventive medicine prevents most ID cases from occurring overseas, and if they do occur, sometimes ID handles it (not derm) and you may never see it. However, if there are any "interesting patients", then they come to Grand Rounds for everyone to see.
Yes, military derm writes up the great cases and publishes them. But they definitely are not everyday occurrences...and I don't think they occur more frequently than civilian programs. You're lucky if you get a great case once a month.
FYI: I have Army classmates in my Derm residency program. They said there are multiple dermatologists in Iraq and Afghanistan (I believe "13"). But only 1 of them gets to solely practice dermatology at the Army Hospital in Baghdad, Iraq. I don't know about Afghanistan. The other dermatologists are deployed to the Middle East as GMO's, NOT as dermatologists.