Statistically speaking in terms of winning percentage its Jeff Reinebold who gets the doughnut for worst coaching record of all time (note the spelling, there's an "e" in his name that everyone always seems to forget.)
Next up is Joe Zaleski. who I am too young to remember. The first Bomber coach I remember was Bud Riley, whose greatest gift he ever gave the Bombers was his son Mike.
What is sad is that we haven't had a coach with an above .500 record since Doug Berry.
https://en.wikipedia.org/wiki/List_of_Winnipeg_Blue_Bombers_head_coaches
The number for O'Shea isn't correct BTW, his win total doesn't include 2016 numbers. Factor 2016 in plus the win on Saturday and he's at 43.6% so slowly getting over .500. Hope he makes it there after this season is done!