Are you, or have you observed someone being, MFFY?  Here are six
scenarios that can determine that.  O-fun....  (this may be a bit
long)

Scenario 1: You need to change lanes to the right, but there is
someone beside you, possibly requiring a pass to pull it off.
A) You decide against the move or drop back.  0 points.
B) You speed up to make the move.  1 point.
C) You make the move, then crush the brakes.  5 points.  An additional
5 points if you flip the bird at the driver you just passed.

Scenario 2: On a multilane section of highway, you see a lane ending
ahead.
A) Your lane is the one ending; you move over behind the line of
traffic in the continuing lane.  0 points.
B) You pass a couple of cars, then make the move.  2 points.
C) You try to pass the entire line of cars until the end of the lane.
3 points.
D) You are in the through lane and move into the ending lane to pass
the line prior to the lane end.  5 points.
E) 5 additional points if the move causes at least 5 drivers to crush
the brakes.

Scenario 3: You are in the left-turn lane at a light-controlled
intersection.  The light turns red.
A) You wait for the next cycle.  0 points.
B) You execute the Kansas City Left (turning on the red): 1 point if
first in line, 1 additional point for each vehicle further back in the
line (2 if 2nd, 3 if 3rd, etc.).

Scenario 4: A vehicle ahead signals for a turn or lane change to the
right.
A) You slow down or pass on the left side.  0 points.
B) You speed up to pass on the same side as the signal. 2 points.  5
additional points if the pass is on the shoulder, or 10 additional
points if the pass crosses an intersection.

Scenario 5: LEO pulls you over for speeding.
A) You apologize to the cop and comply with his instructions.  0
points.
B) You mention a need to have the speedometer checked.  2 points.
Hint: the LEO checked it for you. :)
C) You thank the LEO for the compliment to your vehicle's
performance.  3 points.
D) You have a sudden urge to kick the cop in the teeth.  15 points.

Scenario 6: You are in the left lane of a freeway, passing slower
traffic.  You encounter a suspected LLB.  There is no involvement of a
Clustertruck, nor is there a long line of vehicles in front of
suspected LLB.
A) Speed is below the posted limit: 0 points: you just confirmed LLB.
B) Speed is at posted limit to 5 over: 1 point.
C) Speed is 6 to 15 over the SL: 2 points.
D) "LLB" is going at least 90 mph: 10 points.

The rating scheme!
0 points: definitely not MFFY, but possibly leaning toward JLEDI.
1-15 points: there's a possible need for some patience training.
16-55 points: What have you been drinking?  Hector may switch to that
brand.
56 points or more: GTF off my highway; you are more of a road menace
than Aunt Judy.

Hope you enjoyed this light-hearted survey.  FWIW, I rated myself at 5
points.