B737 econ climb
 

Our OM suggest us to fly economy all the time and best rate during climb. My question is which one is more economy fuel saving, flying economy speed according to a variable cost index or fly maximum rate of climb (best rate)?

I think that the best rate of climb is as it name says, the best you can do in order to reach the desired FL in the shortest time without taking into account $$$ while if you fly the econ you will probably not be doing the best rate but the most efficiency in a $$$ view. If that makes sense.