On a heat-hazy afternoon last April, I went for a post-lunch stroll around the crumbling remains of the 900-year-old Angkor Wat temple complex near the Cambodian city of Siem Reap. That very morning, I had woken up to birdsong and screeching cicadas in the Balinese jungle. And later that night, I’d bed down along a palm-pinned beach in Hoi An, Vietnam . Stitching together a three-country, multi-stop day like this on your own would be a logistical slog, if not a nonstarter. The flight from Bali to Siem Reap alone takes at least six hours and requires a stopover in either Singapore or Kuala Lumpur . Immigration queues, taxi transfers, and baggage checks would easily consume whatever time remains. But on the Four Seasons Private Jet Experience, I soon learned, such “pinch-me” travel days are par for the course. A few days earlier, I had arrived in Tokyo to kick off Four Seasons' Asia Unveiled journey.…