KMC: Two possibilities: The Recreation.gov system is failing to actually send the email, or your email provider routed their email into your spam folder. Check for it there.
If you look at the
Unused Whitney Permits, getting a walk-in (and free) permit midweek in September is not a "leap of faith" in any sense. Last year, nearly all dates had double-digit unused permits for those days. Look at the previous years. They are all similar. Plan your trip. Do NOT worry about a permit!!!
As for other people's leaps: I've never heard of it not working. It is pretty much a guarantee, because 95% of Whitney hikers don't visit this site and don't know how easy the permits are to get.
