The tooltips currently seem to blob everything together, and as of 4.0.1, they were inaccurate. I don't know if 4.0.3a has fix them yet.
WoWhead and WoWwiki seem to end up outdated, and WoWhead doesn't mention anything about SP coefficients.
Right now I'm forced to sit in front of a target dummy healing myself and do linear fits. On that note, sitting with minimal int for a set of low SP data points kind of sucks.