Seemed like an effective semi-quantitative description of the lessened efficiency to me. If bike A with an extra load of about 60 lbs. is still easier to pedal uphill than unloaded bike B, then there's a serious problem with bike B, especially when both bikes have appropriate gearing.

I'm puzzled by the variations in user reviews of the N360 since some users see no efficiency issue while others, like the OP, report very major losses. The lack of data offered by the manufacturer is not reassuring.