I was once on a flight from LHR-SFO with my boss on the same flight. Going to the airport, I knew I had a biz upgraded seat and he didnt. I excused myself saying I have some shopping to do and for the rest of the day played cat and mouse. I went to the SQ lounge even though we were on UA since I knew he would be at the RCC. I boarded last to aviod seeing him at the gate. Since the first two rows on biz are to the left of the entrance to the flight, I never saw him for the rest of the flight and I deplanned first upon landing in SFO.
It was funny to hear him repeatedly ask me my row number the next day since he supposedly went round and round coach class looking for me