I feel people are over, and underestimating both shows here. From a tourist who does enjoy shows (wouldn't book a vacation for one, but if its opening the year I plan to go wouldn't hurt to have it added onto a day), and from a family who enjoys shows but is NOT the theme park nerd I am.
1. I don't think anybody see's "Bourne Stuntactular" and says "oh, no way in HELL am I going there", nor do a large portion say "BOURNE SHOW OMFG BOOK ME 2 WEEKS IN ORLANDO". It is not a vacation draw.
2. HOWEVER, I know from planning with my mom in the past, and with my ex last year, that the shows really help and do. "attract" us a bit. For example, my BF was worried about USF a little because of all the screens, so I explained all the shows and streetmosphere there and he was a bit more sold. We had a wonderful time at USF, but without seeing the marketing of the shows I think felt it was mainly 4-D attractions.
Advertising a brand new stunt show, Waterworld OR Bourne, also 2 entirely different experiences, is always a plus and other than natural costs that come with it, absolutely never hurt. Bourne looks cool but people mainly go to UOR for Potter lets be real, but hearing seeing a highly rated stunt show only adds to their day, and hopefully good word of mouth comes from it. I think the GP fall in the middle somewhere between these arguments.