As @mattnz mentions, it is most likely illegal to split the lane in the manner you describe. While traffic laws differ from place to place, almost any locale with defined lanes will have a law saying that riding/driving between lanes (for longer than it takes to change lanes) is illegal. I strongly advise you to check and follow your local laws. Almost any violation of traffic laws is going to be considered rude.
That said, it often is legal to pass on the non-traffic side of the road. That is, pass on the right where people drive on the right and pass on the left where people drive on the left.
When legal, whether or not it is rude depends largely on what happens after you have passed all of these cars. If you're only passing all of this congestion to turn onto a side road and get out of their way, it's probably not a big deal.
If you pass all the congestion and take the lane again (such as you might be able to do at a traffic light or stop sign), then you just passed all of these cars only to slow their progress and force them to pass you again (which creates more congestion) and is certainly rude.