Yes, but that only shifts the trust from one offline device to the next. You have to know that any of them is properly doing their job. Looking whether the offline verification device is doing its job is not any easier than looking whether the offline wallet does implement ECDSA according to the standards.
So do you think that multisig or Shamir's would solve the issue (as I am not clear how you could ever create a *perfect* system - maybe such a thing is not actually possible)?