This whole discussion sent my brain down a deep, dark path as I thought about the dynamics of ferrofluid in the tweeter's magnetic gap. There's a lot of parasitic stuff going on electrically and mechanically as that fluid moves around. A speaker designer just can't win unless s/he places tight boundaries on the intent of the design.

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated