When SWA pilots talk profit sharing it is an additional payment calculated on your regular earnings. For example, if a pilot makes 200K in regular flight pay (TFP for us or block hours for others multiplied by your pay rate) and profit sharing is 10% then that pilot will be paid an extra 20K via profit sharing. The percentage is calculated to be the same for all employees across the company. So everyone gets the same percent above their regular salary but obviously not the same amount.
How that money gets paid out -- either in cash or into your retirement account gets very convoluted based on personal choices, IRS limits, etc. Suffice it to say that the money is yours and not some IOU check signed by the company -- it is real money either paid as cash minus taxes or put into a retirement account that you control.