^ Not true! You're supposed to sag them, so essentially there is a good deal of room between YOUR crotch and the pants crotch. lol
But 19cm is relatively slim. 17.5cm would definitely be too slim for you, brad. Maybe you would like 21cm... but IMO 21cm doesn't offer anything really in terms of cut, unless you don't have a build slim enough for 19cm... which is often what people buy Dior for. That and their washes.