How do you know the exhaust sound hasn't been finalized?
The videos are not pointless because this is very close to what the final note is going to sound like. Most of that testing was done very early on with the S550 mules and early prototypes. Remember this?
Ford is already prepping FRAP for prototype builds. At this point nearly everything should be very close to production spec.
That doesn't look to me like they're measuring noise level. Manufacturers use mics like that typically for fine-tuning exhaust notes.I don't think they aren't measuring sound of the exhaust note there, they are measuring how loud the engine is for legal reasons. (Cars can't be over a certain noise level) Plus, that was very early in the build. I doubt that was the final test they did on that area.