The preferred method taught in the U.K., as reinforced at Instructor refresher seminars, is indeed to fly a constant heading over a known period of time. This heading is indeed pre calculated on the ground using a forecast wind. When a track deviation occurs then the student (candidate on a skill test) is expected to provide the instructor with a new nominated heading as well as explaining where and when they will regain track. This is the old black art of DR navigation.
Simply flying from from one visual feature to another does not prove the students skill at DR navigation. Accurate map reading is of course a pre requisite good visual navigation skills.
Having returned to ppl flying instruction after airline flying I've quickly seen it's an area where quite a few students struggle. Also like most instructors I've quickly found a few routes where obvious features aren't in over supply.
Phil