Often I think someone is comparing a steel nail with a gold semi-nail....when a nail's a nail....and the same be it gold or steel. I've had a gold 18 K nail....and a steel nail....a nail's a nail.
A semi-nail like a 14 K P-75 when mashed spreads it's tines out to 2X a light down stroke....That would be much softer than a a gold nail......but how can one say gold is softer....when the 18K one was a pure nail????
Myth and BS.
Regular flex be it steel or gold will be 'softer' than semi-nail.
Semi-flex softer than than Regular Flex.
I'd suggest a gold vintage '50-60's) semi-flex nib and both Geha and Pelikan screw out....but for that you need some machinery. Then you must know the nibs are thinner back then by @ 1/2 a width over a modern Pelikan or even a bit more.
But I think that would be too much nib for them....they'd end up turning it into a pretzel....being nail users......
Look for Pelikan regular flex nibs of the '82-97 era....would be safer for the nib.
I have a '50's-60's Geha semi-flex steel nib that is as good as the gold semi-flex ones on my 790/760's, I have steel nibs on my Osmia pre & after war where the gold nib is as good as the steel nib in either semi or maxi-semi-flex....and Osmia is the only company where you can chose between semi-flex...the Diamond nibs...or Maxi-semi-flex the Supra nibs.
Regular flex...Pelikan, my steel 200's and Celebry nib are as good as the regular flex gold 400, 381 & Celebry nibs of the '82-97 era.
Poor steel is not as good as good gold nibs.............nothing says gold much be better made....so good steel is better than poorly made gold nibs...and there are enough of them...........Good Steel is as good as Good Gold.
Was my 18 K Lamy Persona Nail a good nib????????? No, it's a nail....not give, no softness and that at 18 K..............I have a Townsend that I seldom use....in it's a steel nail. A nail's a nail.
The Persona is now a CI. ...........nails are good for making stubs and CI's out of...IMO. Perhaps XXXF
You could offer them a semi-flex but need that ebonite feed to supply ink at a faster rate needed.