I'm trying to check this feature and I must say I'm buffled. I'm monitoring (objectively) the traffic via SNMP and (subjectively) via responsiveness. I do not see any difference at all when I'm switching from standard mode of operation to economy mode on the viewer. Does this require some special procedure?
There are no special procedures required for enabling the Economy mode. Please note, that enabling the "Economy mode" can improve performance in certain circumstances, such as slow/laggy connection. Therefore, if you have a normal connection speed, the difference might not be noticeable.
However, it's not the only feature that can be used to speed up work on slow connections. Other options include:
Disable aero and remove wallpaper
The complete list of solutions that might help to improve connection speed or performance is available here.