Why, oh why am I doing this...
MF, I just watched your linked latest video where you cue up the oft paraded before the peanut gallery Sophie Milman disc. After 5 seconds of play, you immediately declare that the bass is all there. What bass? This is a typical jazz combo with single female vocalist...probably the LEAST challenging genre (for top to bottom freq. resp.) of anything out there. It would be much more revealing if you hauled something out your mythical classical music vault and slapped that into the transport if you want to demonstrate to the handful of us following this train wreck of a thread the full range capabilities of the DL drivers.
And BTW, I think you confuse percussion with bass. Every time you hear a tom or any kind of drum, no matter what the frequency, you conflate it with bass. There was no real "bass" at the beginning of that Milman cut...maybe some upper mid bass at best. That whole presentation had a decidedly midrange centric quality to it and until you see fit to play something with full range content, you'll never really know what the DL shortcomings are.
SET and FR drivers at their current state of the art, will never be the choice for audiophiles who favor low bass content music like pipe organ, EDM, techno, synth, etc. because they cannot pass muster. Yeah, I know, you're a CM man (though we have no evidence of this) so maybe you're fine with rolled off extremities but your tastes, sir, inhabit the minority.