I don't get the benefit of HP filter. If you are going to use a subwoofer and who wouldn't use that in a HT set-up, for which speaker is designed for, then the AVR's bass management will add that HP filter anyway. Technically, the inbuilt HP filter is in fact messing up the bass management of the AVR.
On the contrary I think Arendal's implementation is very sound.
Even without an additional high pass filter you still have to take the natural roll-off of the speaker (bass alignment) into account when building a crossover to a sub.
It is 12db/oct (sealed) or 24dB/oct (BR) of high pass filtering after all, the phase shift of which has a large impact even one or two octaves above where the crossover typically takes place.
Adding an electrical 24dB/oct high-pass filter in an AVR and hoping that it will produce a nice acoustical filter that will complement the low pass filter of a subwoofer is wishful thinking. This is exactly why integrating a subwoofer is a difficult task.
Here you have a loudspeaker with what looks like a 18dB/oct high-pass filter which looks well defined and right where it should be.
Adding an additional 1st order electrical filter and maybe a bit of EQ is all that is needed to form a 4th order LR crossover with a sub for example.
This would be trivial to do, even without measurements if the characteristics of the high pass is known and well chosen.