would anyone go and visit a supercharger for 6 minutes?
Yes, I would (although by the time I had had a pee and got a coffee it would have been longer, and I would have got more range)
My real world range is 220 miles, allowing 20 miles "comfort" that would be 200 miles. Almost all my out-of-range journeys are when I have days between 200 and 300 miles (so max of one stop). Most of those are nearer to 200 than 300, so sometimes I do just need a splash-and-dash.
6 minutes is just short of 30 miles for me ...
For those 30 miles: I have 20 mile "comfort", and I could perhaps drive slow to eek that out to 30 miles, AND it will take a further 5 minutes, or so, to drive into, and back out of, Supercharger ... so 6 minutes charging is a 11 minute detour ...
... but the 20 miles "comfort" is there for whatever might happen on the journey ahead, so (personally) i never choose to eek that out, instead of Supercharging, and running the battery low is not good for the chemistry (although not sure its enough to actually worry about, certainly not "once in a blue moon"), and on balance I would prefer to charge and driver faster and be sure to have "comfort buffer", rather than drive slow. If there was no Supercharger on route then Yup, I drive slow and eek it out
Forgotten what the sweet spot is - drive faster, charge longer but overall time is saved - but the Stats that ABPR has published suggest its somewhere up towards 90 MPH.
The longer I stop to charge, the less then 5 minute in/out overhead matters ...
The fact that Supercharge electricity is free is not something I take into consideration at all (but others might). 27,000 miles a year, and £700 electricity, more than half of which is "free" at work, means that my cost of motoring for the year, and the occasional "personal cost hit" is neither here nor there for me, but might be for others.