This is something I've been noticing while watching players that are great players but poorly effects their game. Have you even seen the players that throw a dart than stop, back off the line and think about things? A VERY high % of the time this NEVER works out well. I notice a lot of Americans do it and some of the Dartslive players do it. If a good player steps to the line, they already know what they are going to shoot at or know what they need to shoot at. Why stop? How can you get into any sort of rhythm?
I think this sort of thing is what puts Americans back a bit in darts. If you walk into any bar on any given night, 95% of the time you will see us playing cricket or as the Brits call it, Mickey Mouse. During cricket players are always stopping to figure out what they need to shoot at. I see this on the professional level as well. People are always stopping their game and standing there like they're figuring out a problem on a test.
Just not good for improving your game imo.
Watch the top professionals play. They stick to 501 and carry on with the game. Only one I can think of that might stop is Kevin Painter. But he only does it during an out shot. I've hear commentators say he shouldn't stop like that as the game is going on. Sometimes he hits, sometimes he doesn't. But the majority of pro PDC players don't do this. They know what they need to do before stepping to the oche and get on with it it.
In conclusion... if you are one of these "stoppers", STOP doing it!!! Your game will improve.