The only type of biscuit I have ever dunked or would ever consider dunking, would be a ginger nut biscuit, as they are too hard for me to bite into and always have been. Mt sister started doing that when we were small and I picked up the habit from her. I wouldn't do it in polite company as my Mother would always tell us it was slovenly, but there have been occasions when the naughty side of me would emerge and I would be tempted to risk it for a biscuit. : ))
Very deep question Roberto, thank you for any insight you may be able to offer.