This is probably why Dan John advocates Tabata front squats. . . I have a love/hate relationship with them.
If you did them and were able to pull an average of 14 reps per round for a total of 112 reps you would have a work output of 70,000 ft.lbs and a power output of 292 ft.lbs/sec.
FWIW you can't compare carying work some distance horizontally to lifing (as comparing running to grace). For humans, it is hard to model the work of standing, walking or running because the effor of standing is ignored (according to these equations, we could stand up for ever). If the exercises are similar in nature (like lifting different amounts of weight) a relative comparison can be made.
For a loose example: doing grace would be more relative to climbing a distance on a ladder or rope (although still not the best comparison).