Brother the answer to this is very difficult. Lemme try to explain
Every manufacturer applies Do's and Dont's to their product usage, in other words, Instructions/Directions/etc ....... in a perfect world you should abide by all the rules and follow procedures. A simple example is like in manual tranny vehicles you have clutch and there is a proper method to release the clutch in order to move your vehicle, now can you follow the same 'proper method' while you are on a steep hill? No.
8 out of 10 times you will end up in screeching sound. Manual and manufacturer says that over-reving engine and releasing clutch WILL result in wear and tear of clutch plate ...... so it all depends how often do we do such off-book experiences.
In your belta, lets suppose you have to apply emergency brakes, you cant just press the brake padel and wait for car to skid 50 feet and then stop, rather I would use brake plus the shifter lever in B mode allowing the engine to hold back vehicles body weight.
Now if you are cruising at 70km/h and some other lush-push belta over takes you, just slide the shifter from D to S and floor the pedal. If it was such a big deal then Toyota should have installed a safety latch between D and S mode ......
Remember there is a difference between two:
1. Can I shift the lever from D to S while vehicle is in motion --------- YES U CAN
2. Should I shift the lever from D to S while vehicle is in motion ----- NO U SHOULD NOT
Source: VWVortex.com - Can you shift from 'D' to 'Sport Mode' while in motion?