Sebastian Vettel and Lewis Hamilton have traded the points lead five times in 12 races so far in 2018. For all the griping about a 'boring' season, only two years have produced more swaps at the top at the same point in the campaign - 1986 (seven) and 2012 (six).
Even with Hamilton carrying a 24-point advantage into the August break, this could be one of the closest world championship battles we've ever seen. And the closer the battle gets, the more significance every little incident and error assumes.
Both drivers have great strengths, but the small weaknesses, the tiny chinks in the armour, are just as likely to decide the destiny of the world championship. Neither is bulletproof, no driver can be, but based on recent evidence Vettel is the championship protagonist with the most clear Achilles' heel.