I thought what I'm about to say would be fairly obvious for most clear bra installers, but apparently it isn't.
This 09 Jet Black E92 came to me recently with a VentureShield install on the entire hood. The first picture below shows the severity of the swirls, which was universal over the entire car. The problem with the swirls wasn't that they were on top of the bra, and if they were, it would be a fairly straightforward fix. Turns out the swirls were underneath the bra and on the clear coat. The installer, who I won't name, attempted to polish the hood before install with horrid results.
I ended up removing the clear bra to fix the swirls. This is the lesson I want to leave everyone with: make sure whichever surface you're putting a clear bra on is 100% swirl free, otherwise you'll be stuck with a heavily swirled surface for the lifetime of your clear bra.
Before:
After:
