Fred Parr just might disagree with you there. Remember the admonitions from his classic steel tutorial for tubing selection based on rider size, weight and strength? Choose one or the other?

That said I like the slant-six myself. It gives one more option to the custom steel builder who might now be encountering potential customers who got their start on 2nd O/S alu or CF reverse sloping bikes and who find the traditional diamond "old-timey".

How many here have seen a slant-6 frame under construction? Because here's pics of what Dazza has been up to. http://www.llewellynbikes.com/thegallery/album44