Vilas,
I see your point in explaining the overspeed protections (ALT* or ALT with A/THR or TOGA in OP CLB), although leaving the levers in TOGA during a normal go-around (where there is plenty of time to notice the LVL CLB message flashing in case you forget) seems an unlikely situation compared to the high energy go-round where you end up in ALT* almost immediately.
Goldenrivett's and my point is that disconnecting the A/THR is not something that isn't allowed. You may call it salvaging a bad situation, but it's basically doing what the A/THR will do as well, but before getting close to the VFE limit.
I agree that you shouldn't end up in this situation in the first place, in fact no situation where the protections have to kick in, but people will always make mistakes and the ability to recover from them without depending on the automation is a necessary skill that I saw was disappearing in the previous company I worked for. (GS interceptions from above messed up, GPWS warnings on a visual part of an approach or at 8NM from the runway, attempted G/A without setting the thrust, etc.)
You probably know which company I'm talking about, but a simple disconnection of the automatics and flying the plane could have prevented those situations. The pilots are the first line of defence, not the protections or automatics.