No, it's not semantics. Your method in this case would combine the low pass filter in the avr's crossover as well as the one provided for on the sub. Crossovers in most avrs are just that, a combination of a low pass for the sub and a high pass for the speakers applied together (thus the phrase crossover, due to the two slopes crossing). If using a crossover in an avr you generally want the low pass in the sub inactivated or maxed out. This is common knowledge. Very very few units can adjust their crossover with separate high pass and low pass settings in the pre-amp (and you still wouldn't combine that with the one in the sub). Proper blending? WTF is that? What do you actually know?