The possible bad experience is a valid reason, but you are thinking too much like critics and not enough like families.
For those of use who are enamored with rollerc oasters our experience revolves around that, but families require more than just that.
It was/is a huge transition that Shapiro is trying to undertake, think about if Disney dropped all that stuff they do and went after nothing but hardcore roller coaster fans. It was all a growing, well shrinking, pains.
That's off topic, but the amount of disposable income for most families dropped last year, and amusement parks are disposable income driven. If gas was below $2.00 and inflation of necessary good like food did not rise as much as it did last year, the numbers would have been better.
It's all trying to fight the 800 lb gorilla that is Disney Land and trying to grab the huge market share they have. It will take time and a lot of effort, and maybe selling of another park like SFStL to Anheuser (sp?) Bush, for them to make themselves competitive with them, and siphon off some of the attendance.