The amount of ascent/descent, the underfoot conditions and the distance all influence how long a walk will take. If all that info were displayed on a junction of several paths the notices would be huge.
The thinking behind displaying the time to reach the next col or refuge must be that hikers don't have to do any calculations for themselves. They are given a single figure. By the end of our first day on the Tour we knew how our performance compared with the calculated times, and thereafter we found it a handy check on progress (but not essential).
Hi Stottie. Agreed. However, the problem I found with some 'time' markings here, is that walks that had them had been marked by DOC (Government's Dept. of Conservation) and different areas had obviously been gauged by different members of DOC, with the result that you couldn't work off a 'standard' estimate.
Maybe the optimum would be to display the mileage plus the estimated time. That way anyone contemplating a wander would have some idea of whether the walk was considered to be over strenuous or easy terrain.