- As to what "learning" is, my overly-simplistic explanation would be "your car watches how much and how hard you accelerate/de-accelerate during the learning period, and adapts the factory preset shifting patterns to hold certain gears a little bit longer or not -- sorta smoothing it out or perhaps improving a perceived lag, for how a more aggressive or passive driver actually uses the car". A more technical explanation of what is likely going on under the covers in the first couple paragraphs HERE may help those that want a mechanical answer.

- This is not something unique to the 3rd Gen RXh or RX, and references can be found in many other Lexus and some Toyota Models (as well as other mfgrs), back for many years

- It's only a discussion point as to how long a new Lexus transmission (or cleared ECM) learns -- be that 200, 1000, or more miles -- or even some other internal measurement. IMHO, perhaps the best, but still non-specific, reference of any official sort is from Lexus TSIB TC005-03 "The effect of the new calibration may become more apparent after several days of driving as the ECM 'learned values' are reestablished from the customer's driving."