I have passed mucoid plaque but done so by colonics alone. I could not tolerate psyllum or bentonite, so I only utilized proper diet and colonics. I did not pass ropes per say but lots of half and quarter pipe black hard rubbery shapes akin to a snake shedding it's skin. Now the interesting thing as well to consider is that some herbal blends with psyllum can be better than others. My colon therapist, my ND and others I have talked with, have had it where not much impacted waste is expelled when doing some psyllum/herb mixtures but then after a powerful synergystic blend such as Robert Gray's formula ,they have amazing results.
To be fair though, there are still others that think colonics by themselves along with good nutrition is sufficient such as Andreas Moritz . He is leary about the psyllum being the rope itself, however it must be removing waste product as psyllum isn't black in colour.
The bottom line is that the colon needs cleansing however you choose to do it. I personally recommend colonics as I think they are very potent.
Consider though, that colonics can't reach the small intestine, so it may be a good idea to use an herbal/psyllum mixture to clean this area.