I have 4 year old twins too! Both of whom are spirited. Must be soemthing about that year????? I kinda read your post lastnight but I was sooooo exhausted I could not see right at all so I wanted to come back and post.
We have the same struggles, and pending on how my dd's are feeling that day. In order for us to go to an outing like that, well to be honest, something like that my dd's just would not be able to tolerate. I would have to at least have a back up plan(ie be ready to leave at the earliest signs of overstimulas), my girls would have to be well rested, well fed, and not sick or ill in anyway, as well as in a good mood. If all these are in unison THEN........
I will try to explain every
possible detail I can. I will explain the saeting, the building, the music(I would try to find an exaole t o listen to before hand) how long the show may be, what I expect of them(to sit) and also to have a plan that if they had to get up before intermission, we would go, no matter what. I cannot expect my girls to sit for long all in one time. I would then, just keep axplaining to them what was going to happen next (ie: going to go stand in line for a drink then we go back to sit ect..) I know with my children the element of surprise will send them right over the edge. I must explain to play out everything new to them, and it really really helps.
I like how you let them play at the park for a while. I think spriited kids need a release of alll that energy they picked up during the excitement. After a good time like you guys had, I would also expect thatyou will run into a spirited child to not be 100% co-operative, thye are ususlly too wired. Thye need time to come down a bit(either that or they crash) I like to be prepared as best I can too(can you tell I may be a bit spirited too?)
I also agree 100% with the book recommendation!