I’d thought that my awful experience at LHR on 14-April could not have been topped. Realizing my physical and emotional exhaustion, the LIS security agents (arrivals) suggested that I request wheelchair assistance for departure on TAP (LIS/LHR) and DL (LHR/JFK). My 20-April security checks went from LIS passport control (great), arrival at LHR fast track transit security check (great) then to baggage claim (TAP refused my tiny soft-sided suitcase without putting it in sizer “it’s expanded” it wasn’t), then to departures security check (out of wheelchair, into 360 x-ray), then to gate, where I was interrogated and ushered into a crowded room with a split-out lane for those boarding directly. Wheelchair was left outside, attendant accompanied me to my seat. It seemed like only US pax were detained. I was called to desk, opened my 2 carryons and purse for physical inspection of their contents, then stood for a wand search, removed my shoes for a swab of my stockinged feet, and swab of my hands. My repeated requests for information were met with only “it’s a requirement of American Airlines and Delta, not Heathrow”. The attendant accompanied me onboard to my Delta One seat - almost the last to board. FAs weren’t aware of extra security and neither were nearby pax. I have a KTN and TSA Pre. No odd identifiers on electronic boarding pass. Can anyone confirm that this is “normal” AA and DL procedure? Thanks for reading.