There are those that advocate placing the trigger in the center of the first joint, then immediately following the first shot, moving the trigger finger so the trigger is centered on the pad.
There is no need to do that and it slows you down. I won quite a few matches shooting my S&W 645 by not changing my trigger finger placement. This included winning the "Walk-Off" where you and another guy walked toward two steel targets. At a random signal, draw, fire and knock yours down first. This was "heads up," where I pitted my 645 (starting hammer down) and my Davis Omega holster against the cocked and locked raceguns from their speed rigs. I won it often enough that others thought that I "HAD to be starting off with a cocked gun.". Doing that had never crossed my mind, but it apparently made them feel better to think so.
To be accurate, it takes more practice than the striker fired guns, but it's not especially difficult to master.