Using the brakes starting to show signs of "warped rotors" pulsations on pedal. I went for some hard driving and stopping cycles to heat the brakes thoroughly and allow to cool down for miles before stopping. Made it a little better. But I noticed hard braking was not really stopping the car as quickly as it should... Turns out this attempt to burn off crud on disc was a stupid redneck approach ... I should have inspected first. At tire change over to summers, I took off front caliper. I've never had the caliper off the car yet in 50,000 km. Why should I, brake pads never wear on this car... right !? I found the inside brake pad firmly encrusted into the caliper and in no way was moving with pedal presses. The backside of the rotor / disc was not shiny and bright and smoothly worn. It was blotchy and mottled and looked like it hadn't been used in a while. So I repeated this, and visited each corner of the car. 3 out of 4 inside pads were seized. 1 on the rear looked like it might have been doing some braking work. All pads around the car had much thickness left to them. As expected, regen saves the wear. Rotors measured over their stated thickness for replacements. One rotor when spun on-car did have a very slight warp where the brake pad touched and created some friction for 1/4 of the rotation but spun freely for the remainder of the rotation. Not enough to cause me worry. I knocked all inner pads out of their calipers using combinations of Moovit parts loosening spray, hammer and punch, pry bar.. being careful (mostly) to not score any of the rubber surroundings of the brake pistons in the caliper, or do other damage. I filed down the crud and rust on the caliper where pad sides are supposed to move, and filed the pad edges... to make some mechanical clearance again so they could move. I used a light touch of anti-seize compound on the filed areas... and when for drive. The "warped rotor" feeling is gone. Smooth stops. And stops in much shorter distances again... Like new. As it should. I have made the vow to pull calipers and check at EACH SEASONAL TIRE CHANGE OVER... This looks like a design problem / prone in my area with lots of winter and road grime conditions. This is one of those things that slowly creeps up on you ever so gradually reducing the braking effectiveness that you just 'get used to it' and brain registers as the new normal, without suspecting anything. I wouldn't expect the Tesla annual service to catch this, they didn't in my case. I was just glad it was something I can do for myself by wrenching on this car. I don't mind that. It was stupid to do hard braking trials without inspecting this first, because that was sure to heat just one side of the rotor / disc .. a recipe for creating warpage. So don't do that.