DH turned 50 last year, and R&C was his choice for his birthday dinner. We made PS ressies for 7:40, I think, and had the 50th b-day noted on the ressie. That day, we stopped at the podium to ask if there was anything special we could do to assure a patio seat, and they said they would try their best but couldn't promise anything. Again they made a note on the ressie.
When we finally arrived 10 minutes ahead of the ressie time, they said they would try and the wait might be a few minutes longer, to which we said, "no problem". We were able to enjoy the British Invasion playing a set (they do Beatles music for those unfamiliar) while we waited for our pager to buzz. Finally at 8:00, just as the music was over, we got called back, and they seated us on the patio with a perfect view. It was wonderful and DH had his wish.
I will note that everytime we spoke to the hosts and hostesses, we were pleasant and friendly, and asked rather than demanded. This is such a popular request that no doubt they get tired of the repeated inquiries and demands.
And one final tip - at the opposite end of the R&C building, to the right of the Fish & Chips take out window, there is patio seating that is fairly hidden by shrubs. We watched Illuminations from there 2 other nights of that trip during the F&WF, and it only got crowded right before 9:00. Both times we got a table to sit at about 10 to 15 minutes prior, and the view was excellent!