What is the difference between "docent" (lecturer) and "Universitair docent" (Asst. Prof.) in the Dutch system? I see many job openings for "docent" or "Universitair docent" on Dutch job boards. Curious, I checked out Wikipedia for more info and, while I learned about the structure there, it isn't clear to me what the differences in the two profiles are. The salary scale is the same, after all.

Also, if I apply for a "docent" position, is it feasible to request that I be considered as a "Universitair docent" in light of my exemplary experience and so on?
"Docent" or "D" or "gepromoveerd docent" is a teaching-only position (or with a minimum amount of research time, like 20%), while a "Universitair Docent" or "UD" is someone who has much more research time (e.g., 40%). 
Also, there are much more tenured UD's ("UD met een vast contract") than tenured D's. 
After I finished my PhD, I was docent for a year (basically because I did not get an UD position), basically teaching a lot, then I became UD, and now I'm a tenured UD. 

While there are some exceptions, a rule of thumb could be that a D-position is a teaching-only and often something temporarily, while a UD position is something that can be potentially permanent and involves research time.