That method doesn't work on the street or in combat but is great for shooting at static targets not returning fire.
Cops get killed left and right trying to sight their target or worst naturally under stress forgetting about their sights and effectively point shooting only not being practiced at as much and missing. Police shooting 'hit' stats reflect as much, cops are at best dismal shots on the whole.
The course I took at S&W toward this type of training covered this and other factoids in detail. Then we really got to see how this is first hand upon going force on force against each other with Simunitions. And this was in scenarios where we knew for sure the BG(s) was going to be there and even in some scenarios which BG would attack first, was armed, and from what direction he/she would be popping up.
Sighted fire for the lose at contact to combat distances as Ducman broke down above.
His description was pretty much what we 'discovered' and were advised to follow and train with toward street level survival. Sighting shooting with conventional sights works (and in class worked) great though when one has distance and time and static targets to fire on such as a BG being behind concealment or thin cover. We covered a bunch of techniques to that end too.
To especially show how sighting shooting is FTL they ran us on a CAPS system which is basically FATS only sourced from a Canadian company and it allowed us to see where our aimed shots were hitting _and_ to show in real time how often times one does not have the pleasure to take the time to sight via traditional means.
I still haven't done the write up toward that class as it will be a tome but it was to say the least eye opening.
Myself I'm normally a pretty good shot, against static targets. Make the targets move and have me engaging/retreating and add to that incoming fire as well and try to sight traditionally...you miss or worst die.
Shemoves if you are looking for how to sight a pistol period as in Basics 101 then go here as it's been covered prior in the 'Newbie' area and reference these two threads...
* ' Everything you ever wanted to know but were afraid to ask' - http://www.gunatics.com/forums/showthread.php?t=325
How to: Gun sights
* 'COMBAT TRAINING WITH PISTOLS (Uncle Sam on how to shoot)' - http://www.gunatics.com/forums/showthread.php?t=390
Field Manual 23-35 - Combat Training with Pistols and Revolvers
If you're looking to game or do extended training then what Duc indicated is a good primer.
FWIW I'm working to adjust my own shooting and sighting methods as I too used to be a front sight type shooter. Up until taking that S&W Academy course and getting to shoot at real people with real guns shooting back.