How can edge rings be selected in a predictable way? When trying to select multiple edge-rings Shift-Alt-RMB sometimes loops get selected in the one (green) way or the other (red) way. 
I couldn't derive a general rule. 

How can two or more face-rings following one direction be selected ?

(Easy to reproduce with a default torus mesh.)
The direction is determined from the edge your mouse is over when you click.

ShiftAltRMB clicking an edge will select the face loop perpendicular to the edge clicked: