to add a thought to that...Bottas was a late signing and i wonder how much of his shortcomings were down to not being as well prepared for 2017 as he could have been, years at Williams would have led him to underestimate what is required of a top tier driver, what it takes to be and stay competitive over the course of a whole season?
i suppose one could say that a season is long enough to get up to speed but i think that also diminishes just how high the bar was set by NR and LH and just how relentless the pressure/pace he had to contend with over this season.
2018 will be the real test, although the one year extension may indicate that he will only have part of 2018 (maybe up until the summer break) to prove he can take the next step.
