Trott had qualified for Middlesex by residence in 1898 after Australia's selectors had effectively cast him aside. The 1899 season was his second full Championship summer. He played 30 first-class matches, bowled 1,455 overs of round-arm medium pace, and batted across the order from three to nine.
The season aggregates: 1,175 first-class runs at 27.97; 239 wickets at 17.10. The 1,000+200 double had been managed before only by single players in shorter seasons (W.G. Grace in 1873 came close but did not reach 200 wickets in a Championship season; George Giffen had done a 1,000+100 in Australian first-class cricket in 1894-95). Trott's mark of 200 wickets and 1,000 runs in a single English first-class season was new.
He repeated the feat in 1900: 1,337 runs and 211 wickets. No one else has ever done it. The closest modern attempt was Wilfred Rhodes in 1909, who fell short on runs. The double would be functionally impossible in modern cricket; the 30+ first-class matches per English season disappeared after 1968.