Lots of very interesting information in this link
A few things really jumped out at me- they say to cook hunks of potatoes in 140 degree water for 20 minutes before cranking up the heat and finishing them to prevent the potatoes from falling aprart. That may be why many of us experience potato fall-out when making potato salad- because we are cooking our spuds too quickly.
They also talk about cooking our potatoes whole in water then peeling for mashed potatoes.
I knew about blanching or par-boiling before freezing and knew to soak chopped or shredded potatoes in salt water before frying but I didn't know a bunch of the other tips so thanks, Marilyn, for posting this.
By the way, I have never used milk in my mashed potatoes- I use butter and sour cream, chopped onions, salt, pepper and sometimes wasabi. A great combo that makes delicious mashed.