Sprint’s decision to enter into a lengthy and costly exclusivity period with the Palm Pre and Pixi was a bad idea. You know it, we know it, and now Sprint is finally admitting it knows it, too. During a conference call with analysts Monday, CFO Robert Brust conceded that “the Pre didn’t work out as well as we hoped” having failed to help put Sprint stop bleeding post-paid customers and fill its books with black ink. Though he was careful to also point to supply issues as playing a significant role in saga, Brust said Sprint learned valuable lessons which it will put to use on its next saviour, the HTC EVO 4G. And simply because there are some rumors circulating that Sprint might play a part selling the oft-rumored CDMA iPhone, Brust said Sprint would “love to have it” but said he was not aware of any plans to carry the mythical device.