Primary rules aren't decided on a case-by-case, election by election basis, and they're not a strategic tool for positioning oneself for the general campaign.

Primary rules aren't decided on a case-by-case, election by election basis, and they're not a strategic tool for positioning oneself for the general campaign. They're an internal process that is supposed to be consistent and knowable beforehand--and the reason Obama was able to upset Hillary in 2008 was because his campaign bothered to learn the rules for all 50 primaries/caucuses, while hers didn't.