I think the other thing not mentioned is that 'frame customisation' more often than not these days starts with a blank sheet of paper, not from someone wanting to modify an existing frame any further than turning a gearie into a fixie or chopping off a few cablestops. That's the only enquiries I get, anyway.

I also find that guys that used to do these types of mods seem to have less and less time for it these days, and would prefer to do new builds. I'm guessing there's just no margin in this type of work, or they just couldn't be bothered for a variety of reasons. Maybe you guys can enlighten me on this?

I definitely think there should be more places offering simple customisation, because I hate the idea of perfectly usable bikes being trashed because the owners can't find anyone to braze-in some new dropouts for them, so from an alturistic POV I think it's a great idea.