Newbie here, and I kind of want to give my 2 cents worth. I do both, down shift to slow to a stop, but never into 1st. Sometimes i will just pull in the clutch a coast to a stop using my brakes, depends on the light or stop sign. If I know it is a long light I will coast, but a stop sign or a light I think is going to change I will downshift.
On the truck relation, I would have to disagree. I use to drive truck for 10 years, owned my own, and I used the coast to a stop more times than not. I always figured less wear and tear on the tranny. It is easier and cheaper to replace brake pads than clutches and transmissions.
Now is there any more wear and tear on clutch and trans using them to slow down 800 pounds on a motorcycle compared to 80,000 pounds with a tractor trailer, probably not, but I think the principle is the same. I would like to hear, and some have weighed in on it, does it reduce the life of clutches and transmissions using them to slow you down? Don't know, like to hear more.
Thanks for your time.