You might be right if we were talking about Catholic ceremonies specific to Catholics in canon law.

That’s exactly what canon law's purpose is.  It’s only focused on the Catholic Church. 
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The doctrine is clear.  ""there can be no valid matrimonial contract between baptized persons which is not also necessarily a sacrament".

This isn’t a doctrine, it’s a legal point.
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Canon law is specifically and only talking about Catholics here.  It’s applying doctrine to CATHOLIC individuals who present themselves TO THE CHURCH to get married. 
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Protestants mary themselves, under a church of their own invention, with no understanding of (and many times a rejection of) catholic marriage morality.  They have no right to the sacraments from a church (and a Christ) which they reject.  Canon law doesn’t apply to them (except in the specific case of a mixed marriage) and canon law was not written for them, only for catholic “canons” (ie the church hierarchy).

That’s exactly what canon law's purpose is.  It’s only focused on the Catholic Church.

You have studiously missed the point. While the referenced text happens to be in a canon law, it is doctrine.

Indeed, the very commentary you cited says this:

"The statement of Canon 1012 on the sacramental character of the Christian marriage does not properly belong to the domain of Canon Law, but is inserted here as an evidence of the right of the Church to legislate in the matter of marriage. The proof of the dogmatic truth contained in Canon 1012 must be left to dogmatic theology."

Stanley, I appreciate this debate and you've made some good points.  Upon further reading, I believe we may disagree due to terminology.  I am partially wrong in my explanations and, from my perspective, so are you.  I am arguing for the practical application of your argument of theory.  Theoretically you are right, but practically, your theory doesn't apply.  Let me explain:
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A.  Per canon law, one who is baptized is a catholic, regardless of if they claim to be "protestant".  So, technically speaking, there is no such thing (in the eyes of the Church) as a "baptized protestant".  She views all those who are baptized as "catholics".  They would then be viewed as heretics, assuming they are Protestant from birth.  Those who are brought up Catholic, but left the faith for protestantism, would be called a defector from the faith, in addition to a heretic.
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B.  Let us also distinguish between
1) who can/could (in theory) receive the sacrament (which is what you are arguing) and
2) who *actually* receives the sacramental graces (which is what I'm arguing).
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Example:  A baptized catholic man, who has not gone to confession in 5 years, confesses his sins to a priest, but knowingly hides a mortal sin.
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1.  This man is able to receive the sacramental graces of confession (in theory), as he is baptized and has gone before.
2.  This man does *NOT* receive the actual sacramental graces because he did not fulfill its requirements.
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Example:  2 "baptized protestants" have a protestant marriage ceremony.
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1.  These "baptized heretical catholics" are able to receive sacramental marriage (in theory).
2.  In practice, this couple would *NOT* receive the sacrament, and the marriage would be null (per canon law) due to the following errors/sins:
   a.  Not believing in marriage for life (both for their own personal marriage, but also as doctrine applying to all marriages).
   b.  Same as above, but believing in re-marriage, for the "protestant heretical" misinterpretation of "infidelity".
   c.  Not wanting children (contrary to natural law), or believing that contraception is acceptable (heresy) and its use.  
   d.  Hiding some other impediment to marriage, per canon law's rules.
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3.  In practice, this couple would *NOT* receive the sacrament (i.e. graces from the sacrament), and the marriage would be ineffective (per canon law) due to the following errors/sins:
   a.  If any or both of the couple is in mortal sin.  The graces of the sacrament aren't effective, nor received, until the couple enters the state of grace.
   b.  Again, most protestants are perpetually in mortal sin for their false beliefs and practice of heretical acts:  re-marriage & contraception.
   c.  Even if the protestant couple were to believe in all orthodox catholic doctrine against re-marriage and contraception, it is highly doubtful they would be in the state of grace, due to the numerous other heresies that protestant sects accept.  
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**Remember, because they are baptized, they must follow canon law and Church Doctrine, in order to receive the sacrament.  The only area they are exempt from, is in not having a valid, ordained minister.  All other catholic morals, dogmas and requirements for marriage must be met, to have a valid/sacramental marriage.**
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Conclusion:  Thus, 99.9% (maybe 100%) of protestant marriages are sacramentally void of grace (in practice) even though (in theory) they *may* have received the sacrament (if they held orthodox views on marriage doctrine).
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Only when the couple 1) enters the state of grace, through a perfect act of contrition, and 2) comes back into the Church fully, can they take advantage of the sacramental graces which they *may* have received (in a potential state) when they were married.