kinukkinuk,
WELCOME TO THE AWS WELDING FORUM!!
Spots sent you to the right 'spot', oh, no pun or fun intended. LOL.
While D1.1, Clause 1.2 does state the 'limitations' it also states that "the code may be suitable to govern structural fabrications outside the scope of the intended purpose."
So, when you go to the 'SPOT' spots referenced in Clause 4, part B, take a look at 4.7.3 in particular. You also may want to make sure you are using a 2008 D1.1. Don't know what changed as I am not looking at my 2006 but in 1.2 the whole thing is underlined designating change. Nothing in 4.7 though.
Have a Great Day, Brent