Copy all text before you comment or post so you can paste it if your submission fails and deletes.
Also, blunt can be rude, but it doesn't have to be. "Can you not let the dogs tangle?" is, by itself, serious and blunt. It sounds like it's possible that you adding additional tone on top of the words is where the disconnect happens.
Sometimes saying "hey, would you mind not letting the dogs tangle? Thank you :)" in a normal voice IS the most blunt and efficient answer. It almost guarantees no pushback. You say it, they do it, done. You saved yourself your current frustration, AND you achieved the goal of not letting the dogs tangle, with almost no extra work.