Sent an email to Floyd Rose technical support and asked about spring positioning. Received interesting response:
"Rob,
There's much debate on spring routing and nearly all of it wrong. The angled outer springs were done for one reason and that's to keep the outer springs from rubbing the walls of the cavity in early Fender guitars. Actual testing shows no change in pitch return no matter how you route the springs. Mathematically, the outer springs exert slightly more force, but it's not a factor in stability.
Three springs is what we recommend with bridge parallel at pitch. It's been proven to work the best.
Jack - Technical Support"
"Rob,
There's much debate on spring routing and nearly all of it wrong. The angled outer springs were done for one reason and that's to keep the outer springs from rubbing the walls of the cavity in early Fender guitars. Actual testing shows no change in pitch return no matter how you route the springs. Mathematically, the outer springs exert slightly more force, but it's not a factor in stability.
Three springs is what we recommend with bridge parallel at pitch. It's been proven to work the best.
Jack - Technical Support"


