That's a total lie/fabrication that perfect contrition is a "substitute" for the Sacrament of Confession, and is directly contradicted from the citation from Trent. One must intend to go to Confession at the next opportunity. There's no such thing as a "perfect contrition" that restores to a state of justification without the intention to go to Confession. Now, Trent adds the phrase about opportunity because it's not necessary to rouse a priest at 3AM to confession immediately after said "perfect contrition", but, say, the next time there are confessions scheduled. But Trent clearly teaches that there is no justification due to perfect contrition alone with the Sacrament of Confession being required, saltem voto, at least in intention. Here's a simple case. Someone makes a perfect act of contrition, with true sorrow for one's sins because they offend God and out of love for God, but then decides he doesn't want to go to Confession, for whatever reason ... too much trouble, embarrassment, etc.
And the claim of an analogy between that and the Sacrament of Baptism is completely false, as Trent explicitly states that there are significant differences between the Sacraments. First and foremost, the Sacrament of Baptism imparts a character and makes someone a member of the Church, whereas the Sacrament of Confession applies only to those who already have the Baptismal character.
Who is this Matheson bozo ... who clearly demonstrates a lack of even the basic distinctions involved here?