On my second trip to Disneyworld, I went all in: 17-55/2.8, 10-22, 70-200/2.8L IS, 100-400L, 50/1.8, and my S100.
I was very thankful that all of the parks had large pay lockers and that I brought a smaller camera bag to bring a subset of my gear.
The S100 got a lot of use.
The 70-200L was used at a handful of parades to get close ups of performer's faces. The 100-400 was only used at a couple of shows. The thing about shows is that using long glass in the seating section can be very distracting to those around you. So I tended to shoot from the edges or rear of the stands.
If I decided to bring long glass again, I'd be sure to bring a second body with a more standard focal range. In my case, the 2nd body would be my X100S.
My other option is to bring my mirrorless setup instead.
Lastly, lugging heavy camera bags all day for seven to ten days in a row is very taxing. I've done it three times at Disneyworld as a challenge to myself. These days, I really value the option of leaving the heavy gear in a locker or hotel room and just bring a lighter kit.
So if you decide to bring the DSLR and heavy glass, don't forget the P&S and a smaller bag so that you can change your options at the least minute. Also don't forget that large bags don't fit very well in a lot of the rides.