If a flag is marked invalid by another user and found helpful by a moderator, the “invalid flag” flag is marked as helpful and is reflected as such in the user’s helpful flag count. If the flag is declined, both flags are marked as “disputed” — even if the flag was declined with a message (in the flags overview, “no action needed” dismisses a disputed flag without a message).
This seems backwards. The more things you wrongly flag as invalid, the more helpful flags (and I’m assuming flag weight) you get. People have also already been confused over the “disputed” result when they flag something as invalid.
Gaming the system like that is easy, too. Flag every flag you can get your hands on as invalid, and most of them will be helpful and none of them will be able to actually be declined. You could have the most helpful flags of any suspended user, possibly!
(That brings me to the other thing — why is there a penalty if a moderator declines a flag, but no penalty if two or more people, including a moderator, decline a flag? Doesn’t that mean it’s worse?)
Please make it possible to decline these and fix the result for invalid flags.