Learned that lesson the hard way after I nearly blew a gasket trying to force a line clear. Now I pretend I'm being smart and patient, but really I'm just too lazy for the big repair job. Works out pretty well most of the time.
Slowing the flow likely let the mud settle so it could be sucked out right. Many people rush to crank up the pressure, which just packs the clog tighter. This shows working with the stuff instead of against it. From what I've seen, that kind of patience saves a lot of trouble later. It's a simple fix that avoids bigger problems.