But lets just summarise it in the fact that VNAV under no known condition will (autonomously) take the aircraft outside its protected range, or else it would not be certified by FAA without limitations.
Wow, you've obviously never flown a B737 in VNAV. You're saying that leaving it in VNAV at 230kts, the aircraft will not exceed 230kts? Yet you also say it selects 240kts to provide a margin for 250kt speed limit below 10000'.
So, again I ask, why 230kts? Why not flap-up manoeuvring speed? At least that would be consistent with a non-VNAV take-off, and would actually do more to prevent 230kt overspeed in this LE flap transit event that everyone is panicking about.