Well, it's more than that. It's specifically forbidden by the rules.Yeah I have my friend's table always but I think its a little disrespectful to run drills while in a match.
I think a better way is to both go on a chess clock.
There used to be a very good player in this area. He would run at least 50 in a typical straight pool match. He would be down for a shot and then he would look back at his grip hand. Take a few strokes looking back at it. Then straighten up and take a few more warm-ups looking at the balls. Then back to his grip hand. Then after a couple of minutes of preparation, he would shoot the shot and make it. (Doc Elliott, for those from this area.) I don't mind if people do that and miss, but he hardly ever missed.
At one pocket, I don't mind if my opponent takes a couple of minutes. It probably means he's in a bad situation and is about to make a mistake. At nine ball where there are hardly ever any choices and at 14.1 where often there is at least one easy way to go on, shots should rarely take more than about 25 seconds.
I think it's a mistake to alter your game in response to slow play by the other player.