I am not peeling nor boiling, have never peeled a potato. Boiling them in chunks I agree won't yield something so much better than dehydrated powdered potatoes - that puts too much water into the equation and makes them similarly gluey. You can microwave chunked potatoes and mash them if you don't have a pressure cooker or instant pot.

Yes it takes longer than boiling water but in the context of cooking other things it's easy and potatoes pressure cooked whole are so fluffy and easy to mash.

I have used the flakes for potato bread, they are useful like dry milk is. But just like dry milk, or instant coffee, something is lost in drying and rehydration.

This is a very subjective prompt though - if the marginal time savings are worth it to you, they are. I don't usually have an urgent timeline for mashed potatoes so letting them cook while I do other stuff works out.

I don't peel, wait to boil, or even mix. I'll literally throw whole garlic cloves in at once, and between the heat and the mashing they'll take care of themselves. It also helps a lot of you have an actual potato masher and you're not just using a spoon or something. Unlike this gif I found though, I just mash them in the pot as they cook.