[CQ-Contest] 2012 WPX SSB - category question

[gp]

Hello all, This is the first year that I'm going to actually submit my 
logs after a contest. Normally I just hunt and peck during a contest and 
I very rarely call CQ. I just pretty much dial around and answer CQ's..  
Well this year I played around with a contest logger and decided to 
submit my logs and see how I did..

I was going through the results and am curious if I have the terminology 
correct.

For example

(USA SO(A)AB LP)


Does this mean US,  Single Operator, Assisted, All band, Low power...  ??

   If you check a DX cluster after a contact to verify a call sign you 
think you might have gotten wrong  does that constitute assisted ?? Or 
do you actually have to use a DX cluster in a way that helps you find 
frequencies of stations (multipliers ...)  you need for it to be 
considered Assisted..