RE: the claim that printed parts are stronger: no way. 3D printed resin is essentially always going to make mechanically-inferior parts compared to something milled from a solid billet; at a microscopic level, cured methacrylate UV resins are porous composites of monomers and oligomers entrapping a large proportion of (depleted, inert, mechanically-useless) photoinitiator. By mass, the resins will always bear a significant proportion of this dead weight photoinitiator material that contributes nothing to the structure mechanically and makes it more spongey than the comparatively-solid mass of interlinked polymer molecules you get with a conventionally-produced bulk material that's then milled to form.
SLA/LCD/DLP printed parts rarely make for good final products, mechanically-speaking, if other processes are available. They're weak, they're UV-unstable and tend to deteriorate rapidly even if post-processed correctly, they're porous and love soaking up water, they're prone to creep under load, etc. I'm generalizing here, but it's a safe series of assumptions for most resins.
Printed parts still offer benefits over milling, though, generally speaking- you can often produce parts dramatically faster, as an entire build plate takes just as long to print as a single part does. They allow geometries that are difficult or impossible to mill, and free designers from many of the strictures you learn to work within for milled parts. 3D printing really shines as an intermediary part of a larger process, that makes good use of 3D printing's significant strengths, while using other processes to avoid its weaknesses. The classic example is printing wax models that are then investment cast- you can produce designs of almost any detail level without worrying about what your mill can do or what tooling you have on hand, and you can print large batches of parts very quickly, then do the actual final product with a process and material that's very robust and reliable.
Same meeting, Ed Harms Sr said he would trust resins when they made a toilet out of one.
