The other jockey somewhat surprisingly above those three legends of the saddle is Jonathan Riddell whose mounts won $3,329,746 in 2011, the season he partnered Jimmy Choux and the Karaka Million winner Fort Lincoln.
Considering Riddell's battles with weight that is one of the truly great performances in the history of New Zealand riding.
Johnson's season has been staggering in both its consistency and relentlessness, with her always cheerful demeanour belying a fortitude which has seen her form barely dip all season.
Without the weight battles that handicap so many other, particularly male, jockeys she has become New Zealand racing's force of nature and, with 15 black-type wins this term as well, she is equal with Bosson.
While any win or even most second placings today would see Johnson set the new record, she finds herself on two of the favourites in the $100,000 Handicap and the $100,000 Championship Stakes.
She is on Markus Aurelius in the Handicap and after he demolished some key rivals in a lead-up race three weeks ago he is a hot favourite even though this is his biggest test.
He meets some of those rivals, like last-start runner-up Cha Siu Bao, 3kg worse off at the weights so is short enough in the market — $2.20 is very short for any horse regardless of form in a major handicap mile, as they provide some of racing's most complex puzzles.
Johnson's ride in the Championship Stakes, Joy Alone, probably represents better value as she was dynamic coming from last in a similar field at Awapuni last start.
She does have the disadvantage of tending to get back in her races but that may not prove to be a disaster on a slow track over 2100m as there are bound to be some very tired horses at the 400m and the swoopers who handle the distance could be able to find better ground out wide.
Johnson has a chance in today's other black-type race, the Champagne Stakes, in which she rides Nest Egg, who ran on well in the Group 1 Sires' Produce at Awapuni last start, suggesting the step up to 1600m will suit him.
Today's other domestic meeting is at Riccarton where Beauden looks incredibly hard to beat in the $100,000 Canterbury Gold Cup.