Well, not all DAO is created equal, and not all who carry DAO are those forced to do so by LE admins. There is a special DAO, in the form of the SIG DAK, which has two reset positions. If the trigger is allowed to reset fully, revolver-style, the pull is as long as the standard SIG DA pull, but 6.5 to 7.5 pounds. If the trigger is only allowed to reset to an intermediate point, the resulting shorter trigger stroke is about 8.5 pounds.
I am an LEO guy who generally prefers DAK SIGs, even though DA/SA was standard at my PD at the time I bought my P229R DAK, in 2004. (We buy our own duty weapons.) I was a rebel in that regard, and had to qual with my SIG DAK only when certain, more enlightened range supervisors were on duty, and avoid certain others, who would have refused to let me qual with DAK. In 2007, the rules were changed to allow DAK as an option. Who uses DAK at my PD? It is certain of the serious guys who run narcotics raids, and train to a higher standard than the patrol guys. And, me, a patrolman who is serious about staying alive.
In my opinion, the LE admins who mandate DAO are ironically the ones who do not understand DA shooting. (In other words, they are doing it wrong.) Those misguided admins think DA is slower than SA, like some kind of speed governor. DA shooting is not slower than SA, unless one waits for the perfect sight picture, and only then starts the DA pull. That may work for fundamental marksmanship training, for beginners, and, let's face it, most LEOs stay at the beginner level. My DA pull starts earlier than that; let's just say my shots break at about the point where a beginner is just starting his trigger pull. (Unless, of course, I am holding someone at gunpoint, instead of engaging in a gunfight.)
FWIW, I did not choose the DAK out of ignorance. I could still be carrying "grandfathered" 1911 pistols for duty use, if I wanted. I like DA enough that I let my 1911s lapse in 2002. I started policin' in 1984 with then-mandated DA sixguns. I have also carried DA/SA pistols, in the 1990s, and have a couple of DA/SA P229s now. All three of these trigger systems work, if one trains to use them. The new systems, such as Glock's "safe action," work, too, though Glocks don't fit my hands, so I stopped trying to master that system; it was fighting Mother Nature. (I didn't need just a grip reduction, but would need material added under the trigger guard and tang.)
