A discussion in the Model 3 section was around the subject whether short and strong regen was more efficient than long and lower power regen. In theory the motor/inverter would be more efficient at higher loads thus stronger, shorter regen would gain a little more energy back. I wanted to dig a little deeper and used 'Scan my Tesla' to read the efficiency at different levels of regen. It shows the efficiency directly as a percentage so it was straight forward to measure. I don't have a Model 3 so I did these tests with my Model S RWD 85. I measured the efficiency at 45 kW of regen power and at 15 kW of regen power. At 45 kW the efficiency is around 87-88%. At 15 kW the efficiency is 83-84%. That alone isn't a big difference. I'd say, small enough to not really care one way or another. But there is more. While I was doing tests, I also noticed that when the car is in D(drive) the car uses aprox 400 Watt more power than when in P or N. It seems the drive unit consumes about 400 Watt just being turn on regardless of motion, acceleration or regen. At 15 kW this is 2.7% loss. At 45 kW that's 0.9% loss. In other words, because there is a constant load, the efficiency looks worse at lower power than higher power. The base load makes up a larger portion. It means the true efficiency difference is aprox 2% less. Strong and short regen might have a very slight efficiency advantage on the motor/inverter. OTOH regenerating earlier with less power means your average speed is a little lower (you are starting to slow down earlier). That reduces air drag meaning you have a little more kinetic energy available for regen. All things considered both method should be almost exactly even. Bottom line: For efficiency it doesn't matter if you use stronger and shorter regen vs longer and weaker regen. Do whatever you feel like! BTW, if you wondered by regen power changes with speed: The maximum regen power I was able to measure was 72 kW when going 110 mph and letting go of the accelerator. From there on regen gradually decreases with speed down to zero at about 3-4 mph. Tesla adjust the regen power with speed automatically. This makes sense as higher speeds 'contain' more energy. 50 kW of regen feels light at 80 mph, but it is very strong at 40 mph. So Tesla adjust the regen power down with speed to keep the feel of deceleration consistent.