They kept trying to add random stories and other strange things to the series. No idea why.
Agreed. It was the exact opposite problem with New Super Mario Bros.
They kept on hoping around trying out different mechanics, but never really stopped to improve anything that had potential. When something new got rightfully criticized, they would rather ditch the mechanic than improve it.
The answer: it wasn't made by the usual Sonic studio, but from an external team of fans turned developers. A video on the topic:
@Bricabrac I know. I have been a fan of Whitehead ever since his Sonic CD port. And I heard before the guys behind Sonic 2 HD were in charge of the level design.
Though, I might check out the video anyways. I doubt I know everything about the game's development.
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