EngoHeel Blister Prevention Patches (2 Patches) by Engo

How hard is it to apply them with wrinkles in a tight fitting figure skate?

Will these adhere to the neoprene sock of a walking cast.

How strong is the adhesive on these? Considering applying them to the inside heels of leather Allen Edmonds dress shoes but want to remove later.

Where do these mount on the shoe? I get heel blisters caused by the top edge of the shoe, but the pictures show these mounted just under that edge.