He's a tanker/air-refueller, the only thing he's probably watching are his fuel gauges.
It's possible that it's intentional, though 'race-track' orbits are pretty common for tankers, and getting into or leaving them can look like that. The erratic motion that is still confined to his assigned airspace and his relatively low altitude tell me he's probably in some stage of his refuelling checklist, maybe crew training or gassing up someone who isn't squawking.