Thus, one could only have or not have a base64 transform, and ObjectReference transforms could therefore NOT be arbitrarily modified. My strong objection is to the Transforms within SignedInfo being viewed as hints. I have never, never, never, never, never supported this option. Hopefully from that which is above and below, you will see how my position differs from this. In other words, I feel that we could allow Transforms outside of SignedInfo as long as the unsigned transforms were applied, and then ALL of the signed transforms were applied.
Applications can decide what unsigned transforms they wish to trust.
It is easy to see how the security of this suggested rule breaks. Simply consider the actual problem we are trying to solve. Since the base 64 decode happens last, all of the transforms are unsigned and there are no signed transforms. Thus, the object can be arbitrarily modified in the unsigned transforms with no possibility of reality checks by the signed transforms. In general, the signed transforms won't be able to run reality checks that secure this method even if they did exist.