370 PQP short and debating a quick mileage run SFO-LAX-SFO. I stumbled upon this thread and wanted to check my thoughts with y'all

1) I can purchase award accelerator under my SFO-LAX trip ID - 2000 miles + 200 PQP for $290
2) LAX-SFO Trip shows the same - 2000 miles + $200 PQP for $290

Is the 'trick' to buy both of these add-ons, and then cancel the flights? Would the 200+200 PQP would post regardless of me taking that flight?

My flights are coming out to $500 as it is, with Ubers and whatnot I feel that the $580 might be worth the hassle. Thank you!