‘Let no man boast himself that he has got through the perils of winter til at least the seventh of May,’ cautioned Anthony Trollope. The English spring of 2013 has made that aphorism appear the height of optimism. Winter’s cold, damp hand only relinquished its grip in recent weeks. The northern summer heralds those most familiar of sporting rituals: Wimbledon, Royal Ascot — and England’s oldest sporting rivalry.