The main problem with cue sheets is they quickly become worse than useless if you accidentally miss a turn, or are forced to detour due to road construction or

The main problem with cue sheets is they quickly become worse than useless if you accidentally miss a turn, or are forced to detour due to road construction or something (which seems to happen to me all the time). A modern bike computer will immediately alert you if you go off course and automatically re-route to get you back on track. Some of the newer ones also get dynamic updates about road hazards.