Not being aware of what is "standard" practice for a very non-standard situation (i.e., ours), I am not sure how this docuмent stacks up. But at first glance and upon a little reflection, I find the docuмent troubling-- it seems much too official and authoritative.
I agree that traditional priests' business will lead them to encounter complicated marital situations among the laity. I have no objection at all to a particular priest, or even group of priests, investigating a lay person's marriage, forming moral certainty about its existence (or lack thereof), and then marrying (or not marrying) said person after determining their freedom to marry.
However, such a process would never be a legal process. How could it be, when the priests in question haven't the authority to make or enforce laws? It would only ever be a private, moral process that a priest (or priests) undertake to determine, for his own mind (being responsible as he is, for witnessing to the integrity of the sacrament), if someone is free to marry.
The docuмent in question does not look like a docuмent agreeing to a private, moral process.