Re: it's already doing 17.46 km/hour
Possibly why us runners tend to use minutes per mile or for the modern inclined minutes per km. I having grown up in metric NZ and being an SI unit using scientist (I have to think about what an Angstrom is) for some reason which is opaque to me still use minutes per mile. Though for a rough and ready 5min/km = 8min/mile.
I suspect it is because most road distance races are 5miles, 10miles, half marathon (13.1miles) or marathon (26.2miles) etc. 10km's (6.25miles) is an aberration in the system. I bow to the track system of course though I haven't run a track race in several decades. Cross country races tend to be approximate due to the nature of the beast, proper cross country races anyway, with sucking mud patches and fences you have to vault with cow pat hazards. Sheep droppings are a mere inconvenience.