clearances for jotul f100 stove (non qt, usa/canada version)

[quicktypez]

Hi,

I'm reading the stove manual and the rear clearance to the unprotected surfaces is listed as

11" for single wall connector
and
8" for "Single-wall Connector with Connector Shields or Double-wall Connector"

the side clearance is listed as

15" for single-wall
and
17" for "Single-wall Connector with Connector Shields or Double-wall Connector"

I found the manual here: (broken link removed to http://www.myerschimney.com/_docs/jotul_F_100.pdf)

I do have a double wall stove pipe. So my clearances are 8" to the back and 17" to the side?

Why is the side clearance of 17" greater for double wall then single wall? Shouldn't it be the other way?

Thanks!