Ok I've done more reading about CM obversations from the BB website (not FF) and I've found this:

EWCM is ‘stringy’ hence coming from the word spiderweb. It may appear as a glob, or in smaller amounts in more watery mucus.

Ok so that sounds good - like what I've described above. But then it also says:

Words women use to describe their fertile mucus include:

Wet
Slippery
Watery
Clear
Thin
Fluid

It's not wet, slippery or clear... Aagghh!