I just saw my MW yesturday and talked about this with her as well. They rather not do it unless you are post dates and really uncomfortable. There is a risk of infection and they don't recommend it if you are GBS+.
The glob o' goo you saw was probabley part of your mucus plug. As the plug continually regenerates itself it is not much to worry about.
The procedure can definitely start labor going if your body is ready, and did with both my boys! With in 48 hours with DS#1 and within 3 days with DS#2. So finish up your nesting just in case!