Just on ECON mode, I have been using it and its effect on throttle input is quite pronounced, my fear, therefore, is that you might be tempted to put extra input in yourself thus defeating the object.
That said, given my driving profile (predominantly short town journeys) I am using B + Econ. I am more interested in the fact that it lessens the Climate Control impact.
I haven't noticed any "learning" effect but I am still in the very early part of my ownership.