I'm certainly not as anti taser as many here. I firmly believe tasers have greatly reduced injuries to both LEOs and suspects. They've probably also reduced the number of deaths from officer/suspect confrontations. Unfortunately, the failure rate in which they fail to produce the desired result is also very high. They do have a pretty good deterrent effect and that should be taken full advantage of, especially considering in most cases there's only one shot.
My best taser capture was when, solo, I confronted a chronic burglar on scene. I ordered him prone under threat of taser deployment (no, that's not how I termed it at the time), while I purportedly held my hand behind my back grasping my taser. After hesitation, he complied and I was able to take him into custody. After handcuffing I advised him that I was glad he complied as I'd forgot and left my taser on my dresser. He had previously experienced a taser ride. So, the point is use the deterrent, it's often there. Most ne'er-do-wells know what a taser is and don't want to take the ride.
I've also seen a number of failures or partial failures. Misses or partial misses are common. Without GOOD contact with both probes you won't get results. Frequently, even with good contact, the suspect will go down and roll and in doing so dislodge a probe, ending the effect. Other times a determined subject, by power of will, can continue to function while under the effect of the taser, although at greatly reduced efficiency. I would think winter clothes would make them pretty non-effective but that's not something I've had to deal with.
So, IMHO, for civilian use, the deterrent effect should be utilized. It should actually be deployed only at a range assuring proper probe placement. It's use as a contact ECD should be understood and trained for. Once deployed, beat feet, as the effect is short lived. Don't depend on it. It's not a substitute for a gun. It's better than nothing.
I think pepper spray works better on dogs. It's harder to hit a dog with a taser. Pepper spray doesn't work great on dogs either but it can, at times, produce the needed effect. Stream sprays are much better than aerosol products unless you're trying to clear a whole room or crowd.
I won't delve into the topic of a tasers entertainment value other than to mention that some subjects that manage to continue to function under the effect of a taser do a pretty good Frankenstein walk imitation. Then there's those that are running full tilt when tagged.