The previous Tuscaloosa thread had a nice discussion about 2nd set openers and an argument that they only push the envelope on certain songs (DWD & CDT notwithstanding). The research department has pulled together some data. Here is a list of 2nd set openers by volume since 2012, when arguably they began pushing the limits at this point of the show more. Special shows (10/31's or NYE) used the 3rd set song for a better comparison.

DWD 21
CDT 14
Golden Age 9
Carini 7
C & P 7
R & R 7
PYITE 5
KDF 4
Tweezer 4
46 Days 3
Drowned 3
Energy 3
Ghost 3
Mike's 3
Sand 3
Twist 3
555 2
BDTNL 2
BOTT 2
Fuego 2
Jibboo 2
ASIHTOS 1
Axilla 1
Birds 1
Blaze On 1
Boogie 1
Character Zero 1
First Tube 1
Free 1
Gin 1
Jim 1
My Soul 1
No Men 1
Party Time 1
Paul & Silas 1
Possum 1
Stealing Time 1
Steam 1
Waves 1
Wilson 1