What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
The pilot, privacy data omitted stated "on earlier flights and taxi tests I had experienced a shimmy from the tail-wheel assembly. I lubed and verified all connections were attached properly/securly. I performed 5-6 high speed taxi tests without any shimmy issues. I flew the airplane for about 30 minutes Friday evening and landed, during the rollout I thought I felt the shimmy again but was not sure. I decided to preform additional high speed taxi testing. At around 30-40 mph the tail-wheel shimmied and broke the right side linkage between the rudder and tail-wheel. I maintained control using rudder only but as I slowed and the rudder became ineffective the plane began a very gradual turn to the left. It was in an area we have used for grass field landings so I decided to let it roll out without risking excessive braking. As I was rolling out my left wing contacted a light." Airman minnis also stated in an email "as you know a pitts is a very blind airplane and I never even saw the light. I did my best and do not think there was anything else I could have done."
As the FAA filed it
THE PILOT, ^PRIVACY DATA OMITTED^ STATED "ON EARLIER FLIGHTS AND TAXI TESTS I HAD EXPERIENCED A SHIMMY FROM THE TAIL-WHEEL ASSEMBLY. I LUBED AND VERIFIED ALL CONNECTIONS WERE ATTACHED PROPERLY/SECURLY. I PERFORMED 5-6 HIGH SPEED TAXI TESTS WITHOUT ANY SHIMMY ISSUES. I FLEW THE AIRPLANE FOR ABOUT 30 MINUTES FRIDAY EVENING AND LANDED, DURING THE ROLLOUT I THOUGHT I FELT THE SHIMMY AGAIN BUT WAS NOT SURE. I DECIDED TO PREFORM ADDITIONAL HIGH SPEED TAXI TESTING. AT AROUND 30-40 MPH THE TAIL-WHEEL SHIMMIED AND BROKE THE RIGHT SIDE LINKAGE BETWEEN THE RUDDER AND TAIL-WHEEL. I MAINTAINED CONTROL USING RUDDER ONLY BUT AS I SLOWED AND THE RUDDER BECAME INEFFECTIVE THE PLANE BEGAN A VERY GRADUAL TURN TO THE LEFT. IT WAS IN AN AREA WE HAVE USED FOR GRASS FIELD LANDINGS SO I DECIDED TO LET IT ROLL OUT WITHOUT RISKING EXCESSIVE BRAKING. AS I WAS ROLLING OUT MY LEFT WING CONTACTED A LIGHT." AIRMAN MINNIS ALSO STATED IN AN EMAIL "AS YOU KNOW A PITTS IS A VERY BLIND AIRPLANE AND I NEVER EVEN SAW THE LIGHT. I DID MY BEST AND DO NOT THINK THERE WAS ANYTHING ELSE I COULD HAVE DONE."