I am not saying you or anyone else has to worry about the crankshafts breaking,just that is the weak link in that particular engine.
Has the Frenchtown flyer broken 300 cranks?
My friend builds cylinder heads & has feedback from customers on Ford 300 engines.
Now if I hear you correct,,,, you have heard of 300 cranks breaking????
That being said,,,, have you heard of 200 or 250 Ford cranks breaking????
I am making a point here,but it seems you do not get it.
MBHD