MO and Signature

What is MO and What is Signature?

Are these really inseparable issues as is so often reiterated? MO, meaning method of operation (modus operandi), is said to include ONLY the actions to commit the crime. The "crime" is supposed to neatly fit in one of the legal categories such as robbery, burglary, theft, rape or murder.

Motive is closely related to the concept of MO in that motive is the reason what picks a particular crime to commit. However, offenders do not in actuality have motives that match the categories used in a court of law. Offenders do not say "Hey, today I want to commit a rape which includes the sexual penetration by the penis of the vaginal cavity of a female." More likely they will think, "I am going to teach that bitch a lesson." Teaching a bitch a lesson has not yet been classified a crime, but that is the purpose of the action he is about to take. So, if his "crime" is going to be to "teach a bitch a lesson", what would be the MO necessary to commit that "crime"?

If the offender's motive is "to be the victor in the battle against evil", what MO would be necessary to commit that crime? Is it to simply murder a woman? Is that all it takes to win the battle?

What if his motive is to prove he a man "to be obeyed, worshiped and respected"? What level of MO is require to do that? Force? Rape? Humiliation? Pain? What if he is sexually aroused by pain? It's the only way this guy gets off.

Is it signature to go further than "simple" rape or "simple" murder when he tortures the woman?

As you can see, like so many classifications, these labels are sadly simplistic. If MO and Signature were placed on a continuum, at what point does the offender cross over the line from doing only what is necessary to commit the arbitrarily defined crime to doing what expresses his personal emotional needs and fantasies.