Before revision:  The most remarkable finding from our studies is that , for a given cargo size, the swim-speed is maximized when the rotational drag coefficient of the flagella is tuned to the torque-speed  characteristics of the bacterial flagellar motor . This tuning criterion discovered in our analysis is not satisfied by wild-type bacteria such as E. coli .
After revision:  The most remarkable finding from our studies is that , for a given cargo size, the swim-speed is maximized when the rotational drag coefficient of the flagella is tuned to the torque-speed characteristics of the flagellar motor to maximize the bacterial swimming speed for a given load. This condition is independent of the geometric optimality condition derived by Purcell and interestingly this condition is not satisfied by wild-type bacteria such as E. coli .