Potatoes boiled with skin on makes less gluey mash?
I've never heard that boiling potatoes skin on makes a difference in consistency, but it's possible. The skin will act a as a barrier to moisture, letting the potatoes cook while absorbing less water. That will only work if you keep the potatoes whole though, cutting them up will negate that somewhat. 

While skin in may make a difference the choice of potato makes a bigger difference. Waxy potatoes are not a good choice, neither are dry ones like russets. A medium starch potato is best, like a yukon gold or a maris piper.

Also very important is preparation after cooking. I find using a mixer tends to overwork the potatoes and make things gluey, while most chefs would recommend using a ricer. A ricer does give a great result but it is messy and lots of work. I use a potato masher and do it by hand, which to me is a good balance between speed and cleanup while giving a good result.