Re: 15 to 16 Mb per lap
The data collected is optimised to what they can realistically be analyised within a lap before the next load of complete lap guff downloads. 13 years ago there was one analysis bod examining each car in limited detail and looking for obvious 'oh crap that widgets gonna break' details. When this happens other 'spare' analysts would step in and examine the data more closely whilst the original analyst moved into the next laps data.
Some of the sensors would be as dull as what gear is selected or gear box temps which don't need 'that' much sampling or generate that much data but things like revs or driver excuse preparation would.
As there is now a whopping amount of post race analysis I would imagine that the granularity of what is actually downloaded from the car at the end of the race is much larger than 15mb a lap that is gathered via telemetry.
The telemetry was radio woowoo that I never got to grips with.
That being said I never really liked the racing, the magic at the factory on the other hand I really do miss.