We have a small victory!
If you are going out in public then you wear underwear.
I am happy with this compromise. Crash on the other hand still wishes underwear did not exist. For the past few days if he wanted to go out with everyone, he wore underwear. Granted there was still rolling on the ground, screaming, and an entire grave yard of unacceptable underwear. But, he did it.
And my stress level has dramatically decreased. No more arguing. I just say you have a choice. You can wear it or not. It doesn't matter to me. Then I walk away. He is completely capable of dressing himself and he knows better than I which is acceptable underwear and which is not. He doesn't need me to watch the minor meltdown that it takes to get dressed.