Yamaha DTXpress/DTXplorer/DTXtreme

Guys,
Last night I saw the Dixie Chicks and they had Joan Osborne with 
them as opening act...the Chicks were AWESOME by the way, don't let 
anyone fool ya-they kick butt as musicians...DESPITE all the 
contraversy!!  Anyway...here's what Joan Osborn's drummer had for 
his acoustic set up (dw kit)...he had 2 cymbal mounted 
TOGETHER...looked like he had an 18 inch Zildjian ride (hand 
hammered), and UNDER it mounted UPSIDEDOWN (and no...it was NOT a hi-
hat) was what looked like a 14 inch crash cymbal-he used this 
particular set-up for his ride....then he had ANOTHER IDENTICAL set 
up for his crash/ride...it looked like a 14 in or 16 inch normal 
mounted cymbal with a 6 or maybe 8 inch SPLASH cymbal mounted UPSIDE 
DOWN in the same fashion as a HH...THEN....it gets wilder...he had 
what  I would say was a 24 inch bass drum and ATTACHED TO THAT 
SITTING IN FRONT OF THE regular bass drum was a SKINNY(what looked 
like a marching band bass drum)...there was NO pedal attached to the 
skinny bass drum, it just sat there and you could see it was 
functional coz you could see it absorbing his kicks-I couldn't tell 
if it had any head on the side mounted up to the 24 inch bass, only 
the regular 24 inch bass had a kick pedal.....the sound was what I 
would call deep, and yes...you could use the word LAYERED on all of 
these 3 wierd mountings....my question is this....Have any of you 
guys seen this kind of set up and what IS its purpose?  I am really 
anxious to find out.
Jade