Hi, Favbless,
Good question. Now, I'm basing my answers on my own experience with FSW, not QSW......although I think it might be applicable.
I applied under the NOC 3111, because I felt I had a better chance of being chosen, and the cap was slower to fill than the NOC 3112. (I am qualified for both). I have a friend in similar circumstances with me, who decided to go with NOC 3112 because he wasn't qualified for 3111. The only way could have applied for NOC 3112 was to include his NYSC year as work experience. And he qualified, because he got PER.
Based in this experience mine, I think the answer is YES, at least for FSW. The important thing is how you describe what you did in your forms, and the reference letter you get from where you worked. They must match the job description of that NOC you are applying for. And it must be UNSUPERVISED, that's why internships IN MY OWN OPINION may not qualify.
I will crave the imput of other seniors in the house, especially the QSW stream on this issue.