Part of the problem is that the military is still a bloated bureaucracy. We have more generals of all ranks now than we did in WWII. Those generals have commands and they have staffs. We have a senior enlisted adviser, as I just learned, for the JCofS. In the 60s we created senior enlisted positions for each service. They have staffs. About ten years ago the SMA sexually harassed a member of his staff - another SGM. If I were King for a day, I’d do a lot of cutting.
That said, it was the administration's decision to rotate units rather than mobilize the country. We could have built a military like we did in WWII. We didn’t.
During Vietnam, once all the units were in place we sent individual replacements. The tour was a year. Lack of cohesion became a factor. I went over with a unit of the 4th ID for my first tour. My second tour was as an individual replacement to be assigned by USARV once in country.
Sure, we could have assigned all of our combat troops to Afghanistan and Iraq back in 02 and 03 and, unless you were killed or wounded, you stayed there. Just typing those last two sentences makes my blood boil. If you or anyone else thinks the Army is stretched too thin right now, I don’t think you could even imagine the repercussions had we done a “for the duration” policy.
Some of my thinking comes from watching and trying to understand what the special forces are trying to accomplish. I have seen coverage of a commander in Anbar with a diagram he made of the local tribes that covered his wall. Whatever headway and understanding he made was mostly lost when another crew rotated in. Changing personnel often does not enhance efforts to form relationships. Of course to those who want carpet bombing to make parking lots, it wouldn't matter.
As for your blood boiling, it reminds me of a ret Master Sargent I used to employ in my company. He liked to complain about his retirement benefits, but I told him he was talking to the wrong person. Although I acknowledge that the armed services must keep their word, such does not communicate well to those of us in the real world who may also serve our country without any such perks.