I would disagree with the equipment conclusion but totally agree with the complexity issue and the average police officer issue.
In reality, the average officer will not develop the skill to appropriately use a hand held light in congunction with a pistol. Lets look at about every body cam video where an officer attempts to use a handgun/light technique where the light is near the gun. Where is the light pointed? Mostly at the ground. That's because under stress we do what we're used to and we mostly train to grip the gun without the light. It's motor skills 101 but law enforcement calculus and trigonometry plus astrophysics. Switching for most cops doesn't matter at all becaus the light won't be pointed at the threat anyway... it will just make the user a better target. Yay.
Techniques taught must be simple and equipment should echo simplicity. Momentary only works well for this. Training should include the minimal number of techniques necessary to accomplish the task so that the repetition necessary to build skill (which will still be inadequeate) will be as focused as possible. I've seen "clicky" lights on when they shouldn't be (a lot) and off when they shouldn't be (a lot). Momentary exhibits the same problems, but is more in tune with what we know (push the gas to go, let off to slow/stop) as opposed to the extra click when you pushed too hard or didn't push hard enough.
Interestingly, I recommend the opposite for a weapon mounted light. Toggle switches suck under stress and are very rarely used. If they are used, constant-on is the best for allowing the mental working memory necessary for the fight. Pressure switches are much more applicable for basic patrol use but because some administrators and a poorly though-out Force Science article think that pressure switches equal negligent discharges they are not so common. What is common is shooting the wrong person in the dark. It happens. It happens more than those administrators would admit, but it's easier to justify killing the wrong person in the dark than it is to train people to use the tool that would prevent that.
That's not just for cops... Regular people shoot the wrong people too. The problem is that if they had training it's usually from the cops who have the same bad habits. We can and we damn well should be better. If a motivated non-cop wants to learn to use a light the right way, they need to be very careful who they approach for training.
I'm happy to hear the Sig class addressed some of this because I've had good experiences with their training in the past and I've had some VERY bad experiences with low light training from other entities.