What you can say about lowbass and midbass perfomance for high end loudspeakers ?

i listen Egglestonworks Viginty  and find out the play increadable bass performance , especially punch bass
The company claim the two 10" woofer working as  passive sub with cross point 100Hz, and 2  6" midwoofer is
responsible for midbass get very good punch bass,  They say to produce good bass the need to split bass, becouse  
low base woofers get big moving mass cone , and work poor for punch work (too heavy )  Do anybody agree?
But this issue can be find in big speakers with 10"-12"woofer, For small floorstander is not applicable