Yeah - I figured the author of the original question didn't know the difference, and that he/she meant butting instead of "rifling". Particularly as there is no such thing as "rifled" frame tubes. And since either butting or splining could reasonably be referred to as "rifling", then my answer was appropriate. Kind of like them asking "is it blue?", and me answering "yes, it is cerulean". So, a more specific answer to a more general query. Thanks for the incorrect grammar lesson though - really helps identify the frame!