[leetharris]

A breakthrough in tunnel cost and speed per meter. Have you read into this at all or is this just another snarky comment?

[Supermancho]

Almost every bored tunnel project has unique constraints. Lots of breakthroughs could be achieved by ignoring regulations and external considerations. This is not innovation or a particularly interesting result.

[idiotsecant]

This 'breakthrough' appears to have mainly been achieved by ignoring health and safety regulations. Not so impressive.

[jmuguy]

I've seen Musk and TBC make those claims, I haven't seen evidence from the industry that they're actually having an impact.