Most sports writers agree that drivers have (at best) a period of 5 years in which they are in their prime, just as most athletes. During this time frame, experience, racecraft and raw speed are universally high and overall well balanced. After this period, raw speed (which is based on reflexes, stamina, concentration, motivation etc.) declines while experience and racecraft may increase but only serve to compensate. After that reaches a plateau, overall competitiveness declines (from a very high level in case of some drivers) and a new generation of drivers surpass the old (in speed if not results). While it may not be readily recognized at the time, in hindsight the period of decline can usually be accurately pin-pointed.
Nelson Piquet was arguably in his prime from 1980 to 1984 when his driving was top notch. Alain Prost’ prime years were probably from 1984 to 1988. Ayrton Senna was at his height from 1987 to 1992. These periods might not have been their most succesfull or they may have had good seasons later on, but during this timeframe, these drivers were IMO at the height of their abilities. (And it nicely follows the 5-year maximum of primeness

Returning to Schumacher, it can be argued that Michael entered his prime in 1995. Before that time there were the occasional mistakes, self-inflicted or instigated by his teams, and a certain juvenile inexperience common to all drivers at that stage. But from 1995 onwards even the rabid English press had to confine their attacks to his (lack of) sporting ethics and personality as his driving was simply beautiful. His already low mistake count became even more pronounced and MS seemed to be a more complete “package”. Something I would not say of the MS of 1994.
Adding the 5-year maximum to 1995 would place us firmly in 2000 as the year that Schumacher’s powers start to decline. Decline in a driver doesn’t mean he forgets how to drive a formula car, it simply means that his abilities lessen. As Nikki Lauda proved in 1984, experience and racecraft can compensate to a certain extent but Nikki would be the first to agree that he couldn’t compete with a young Prost on speed. A lesson Prost learned himself in 1988 and that he applied in 1989, beating Senna.
So can we see that Schumacher is declining? Is he perhaps not as fast ast he used to be, despite the many excellent race victories in 2000 and 2001 and one and quite possibly two worldtitles? Is Barrichello’s nearly equal speed in qualifying (on occasion as Barrichello is somewhat erratic) but not in racing an indicator that Schumacher is slowing down and using his experience and racecraft to stay ahead? Or does it just mean that Barrichello is actually bloody fast and if he had Brawn & Co behind him he would be showning MS a clean pair of heels? If, at the end of Schumacher’s career, we could all see that the 2000 season had been the moment that Michael moved out of his prime, what would be the indicators we would agree on?
What sayeth the learned forum?