Morning Scott,
Don't try not reading back or complying with tower instructions in the US... It wouldn't be smiled upon...
Agree that we must comply with all tower instructions (like "report downwind") but didn't think in the US it was necessary to readback "report downwind". I only thought we had to read back a "hold short" instruction when VFR at a towered airport?
Generally find US tower controllers very reasonable when dealing with alleged pilot errors....
Regards