the purpose of separating the cpc's into separate terminals is in case 1 becomes loose or snapped, you'll still have earthing (protective and functional) to equipment .
Yes, I understand what you are saying and don't dispute the point. If you think about it, one or two terminals can suffer the same fate.
I was trying to explain why problems can occur with RCD protection on modern equipment (e.g. computers with switched mode PSUs drawing several amps at 230V) - by design, current will flow through the cpc and unbalance the RCD. Not everybody understands that.