I've been taking that twice a day for ages. I think my colon is just lazy, because even with a high fiber diet, things dont move as regularly as I would like. Far less problems while taking that stuff.
Part of the problem with taking anything like has been mentioned, psylium husk, etc., routinely is that the bowel does get lazy and gets to depend upon the chemical action to make it work.
And it's also true that daily movements of the bowel are not necessarily needed for one to be considered "regular", more than a few people have BM's once every two days, or longer, and are still considered normal and regular. It's a myth that you have to dump every day....but the U.S. does seem rather anal about moving its collective bowels, hence all the commercials about regularity and colon cleansing and that crap.
Before the doctors could put the instruments up the scope you didn't have to be sterile inside. If he needed it cleaner the doc could send warm water up and suction it back out. They want you sterile and anesthatized now because they can put instruments up the scope and cut out anything they don't like the looks of immediately. Surgery is part of the colonoscopy.
They do not sterilize the gut. Too much bacteria they want to keep intact to want to sterilize the gut, and the preps they use for emptying the gut for a colonscopy don't sterilize it.
And the "surgery" you allude to is usually only biopsies and polyp removal, both of which are snip and cauterize blips. "Real" gut surgery still requires opening the gut....talking about bowel resections (for cutting out cancerous sections of the bowel) and the like, esp. for cancers or diverticulitis. But taking a biopsy or cutting out polyps isn't really considered surgical intervention, not in the "classic" sense, and the gut isn't required to be sterile for those procedures, just "clean". (Speaking from experience both as an RN and as someone who has had more than a few colonoscopies and biopsies done. And I assure you my gut was not sterilized.)
In fact, while sterilizing the gut does happen, it's usually secondary to a very aggressive antibiotic regimen, usually admin'd. IV, and it causes problems with horrible diarrhea. Sometimes the normal flora of the gut refuses to re-establish itself from the prolonged diarrhea and I've seen "shit" enemas administered in attempts to re-establish the gut's normal flora.