So – 2×10 good, 2×9 bad. That’s because most peoples 2×9 is actually 3×9 with a bashring. Rather than 2×10 which is actually 2×10.
My 2×9 is er 2×9 with a bash; a double specific SLX.
Brant, Neil advised that fitting a double specific front mech would avoid the issue of the mech hitting the chainstay and gouging a piece out, it hasn’t! the mech cannot be run low enough to avoid the chain rubbing without hitting the chainstay on full compression, bad design flaw.
Awaiting solution feedback.