For most subjects at the university level graded homework (and graded attendance) has always struck me as somewhat condescending and coddling. Either it serves to pad out grades for students who aren't truly learning the material or it serves to force adult students to follow specific learning strategies that the professor thinks are best rather than giving them the flexibility they deserve as grown adults.
Give students the flexibility to learn however they think is best and then find ways to measure what they've actually learned in environments where cheating is impossible. Cracking down on cheating at homework assignments is just patching over a teaching strategy that has outgrown its usefulness.