G'day Simon,
Don't loose any sleep over the timing side journal size. Trihards use a near identical crank with 30mm ( 1.181")
timing side & 1 1/8" ( 1.125") drive side . The T140's put out a bit more poke than most A10's.
I've never heard of one braking in normal use.
As Musky suggested, you need to check the blending radius where the journal meets the cheek (a sharp corner here will almost certainly lead to a breakage.)
The crank pin radius mentioned in the service sheets ( 0.090" ??) may be something to aim at.
If you were here in oz I'd offer a swap for a standard crank, it would save me some machining on a roller project in the pipeline. Postage is an absolute killer though.