not misinformed. If the procedure is experimental, it should be explained that way. Normally there are more work to do when it is experimental and even more if pateint is enrolled under a protocol. concealing the nature that it is experimental when it actually is is problematic. When it is experimental, you can never be certain of the actual success rate, right? to my knowledge, it has never passed the stage of experimentation.
It boils down to what information was provided to patient.