Is dropping u in ですね/ですよ a special case?


So I never though about it, but ですね and ですよ don't follow the silent vowel
rules, but I don't think I've ever heard (desu ne) or (desu yo). It's always
(des ne) and (des yo). Unless I'm imagining things, is this right? Is this
some special case? Or is the u actually said with ね and よ?

