My question is would it be best if a soldier goes to the promotion board before or after WLC?

I was promoted down range before I attended WLC. And I was at a STAGGERING disadvantage. WLC and the classes in it provided me a framework to actually BE an NCO. I am not saying it is impossible it is just harder. SSD1 and WLC gave me the tools to be a better leader.  Go to WLC first. All the info there will help you excel at the board and as a leader. 

Back in the olden days, lol, an individual was sent to the promotion board prior to attending WLC, as you had to be recommended by your leadership to move up to the ranks of the NCO. As we were an Army at war and so many people were unable to attend WLC due to deployments, there were many open seats that became open and were filled by non-promotable SPCs in order to ensure that the NCOAs were still operating. As we transition back to a "garrison" Army, once again it will settle back into this routine as the automatic promotions lessen and less and less non-promotables are allowed into WLC. Some people are ready to attend WLC prior to being boarded, others need to know the baseline basics of what is required before they attend the foundational NCOES course.

In my opinion; it doesn't matter, because we're upheld by a set standard and you shouldn't have to go to wlc to learn those standards. what it does help with, is teaching you how to uphold those standards. You should be able to perform two ranks up and one rank down. A spc ready for the promotion board is a spc that is seasoned enough to become an nco. Given you won't know everything but the confidence, understanding, and ability to solve critical situations should be present. With that said; in my personal experience I went to a soldier of the quarter board, attended wlc, then went to my promotion board. Wlc should be a refresher not the main source of your knowledge base. It does however help you learn the creed of the non commissioned officer, Winning. -sgt le