any validity to this short range/battery test?

I don't have access to a LeafSpy and I'm checking out a 2015 with less than 10k miles on it. So I went on a 17 miles test drive. Here was my EXTREMELY rudimentary test (was round trip obv):
With the AC set on at a very comfortable level the initial readouts were 98% and 84 miles (implying 100% should be 85.7). I drove a VERY hard 17.0 miles with hard starts and stops and many of the miles at 60-65. At the end the readouts were 75% and 68 miles (implying 100% should be 90.7).

Please be gentle, any positive takeaways at all? Snide or rude comments can be left out please, although I've been impressed with this forum, so not expecting any. Thoughts?

I find that hard starts are not detrimental to range while hard stops (which waste energy by using friction brakes) are more noticeable vs. less aggressive stops that take advantage of regeneration. The air conditioning is quite efficient so it does not have much impact on range. The distance to empty (DTE) display (called the GOM for guess-o-meter on this forum) is not very accurate so I will ignore those numbers. The SOC percentage display is fairly accurate and went from 98% to 75% in 17 miles so you used about 1/4 of the range. Therefore, you could expect full range under your driving conditions to be between 65 and 75 miles. I expect you would get the first low battery warning (LBW) at about 50-60 miles and very low battery warning (VLBW) 5-10 miles later.

Based upon the information you provided, I am guessing that all 12 battery capacity bars (10 small white bars and 2 small red bars) at the right side of the display in front of the steering wheel are illuminated when the car is on. I am also guessing that the car still has the original tires at 10k miles (16-inch Bridgestone Ecopias on S or 17-inch Michelin Energy Savers on SV or SL). If so, then the battery appears to be in relatively good condition for a car that is 2 years old. Additional concerns when considering used LEAFs are the climates that they were in because battery deterioration is higher in high ambient temperatures.

In the future, use the more accurate range estimator. It can be accessed by pressing the blue button on the steering wheel. Two ranges will appear, inside concentric circles on the Nav screen. The higher number is the GOM estimate, while the lower number is the realistic one. You have the right idea, but using the GOM won't work - its number is determined by the previous several minutes of driving before the car was turned off, and so the initial reading isn't helpful.