Lasers, IMO are best for two purposes:
-helping one to observe poor trigger technique (that shaky dot thing)
-"aiming" when in a tricky position (around a corner, from the waist, etc,)
However, a laser sight must be zeroed-in at a chosen distance. Most lasers are offset from the barrel by at least an inch, sometimes more. One can either aim the laser to be parallel to the line of the barrel (thus an inch or two offset at any point downrange), or one can aim the laser to intersect the barrel line at some specific distance (probably 3-10 yards is a good choice).
Did this geometry lesson make sense? I hope.
One suggestion I have been given, though, is to always train by using the iron sights, trying to stay focused on the front sight and NOT the laser point.
.45acp, .40 S&W, 9mm, .38 Spl, .380 acp, 22lr
12 gauge, .223/5.56x45mm, 30-30 Winchester
2 Chron. 7:14 Christians must seek His face