So in VS mode you airplane will try and maintain the airspeed you have bugged and the VS you want? But it will set VS as priority and “try” to maintain bugged speed but like you said a high rate will make you blow past your speed?
Yes, exactly, it will maintain the V/S rate and the A/T can only work within the range of IDLE to the REF THRUST in order to try and maintain speed, but it cannot if you are calling for a high rate of climb or descent...