WP:3RR was changed (without there first being consensus) back in April so that reverts count towards the 3RR even if they are unrelated. This has resulted in some editors playing "gotcha" by invoking the 3RR without first giving a warning.
I'd like to propose the following exception to the 3RR policy:
Exception:
Lack of warning
A 3RR ban cannot be imposed against an editor who has not been warned that he or she is in danger of violating the 3RR. A ban can only be imposed when an editor violates the 3RR after receiving a warning even if he or she has already tecnically violated the 3RR prior to receiving a warning. ---- This policy is already implied on ANI:3RR which states: "If you find yourself in a revert war, it is a good idea to ensure that the "other side" is aware of the 3RR, especially if they are new, by leaving a warning about WP:3RR http://en.wikipedia.org/wiki/WP:3RR on their talk page. Administrators are unlikely to block a user who has never been warned."
Unfortunately, admins seem increasingly willing to block without regard to warnings, a practiced that assumes bad faith.