Hate to break it to you, but those ropes that you speak of. Psyllium is pretty much what those poop-ropes are. If you look closely, there is a yellowish-rubbery-core, with pieces of poop attached to it. The psyllium is what the yellowish core is.
Psyllium works by absorbing alot of water, and expanding. The combination of water and psyllium produces a substance called mucilage, which is similar to adhesive glue, and attaches itself to the fecal matter thats in your large intestines. That's why the outer layer of the ropes are poop. This process is very similar to what Bentonite Clay does, which you mentioned.
So, at first glance, it appears to be a long-piece of poop, but it's actually two layers. The inner layer is the psyllium that has been pushed thru your system, the outer layer is what you would've pooped out anyways.
I'm not saying that psyllium has no medicinal benefits, because it does if used properly. Alot of people I know use psyllium instead of fiber, because it essentially works on similar principles. Colonix has a good formula, so if you feel better from the use of Colonix, then great! I would keep using it.
Since Oxypowder is an oxygen colon cleanser, it doesn't 'bulk up' like psyllium/colonix does, Oxypowder is the opposite, it 'melts' the facal matter. That's why you never saw any of the impacted fecal matter or mucoid plaque come out. Many people beleive that oxygen colon cleansing is more effective at reaching the deep folds of the intestines, the places that psyllium or bentonite clay can't reach. But that all depends on who you ask.