Another thing I love about the Three Forms of Unity (TFU) is that they are pre-modern documents. The Belgic Confession and the Heidelberg Catechism were written in the 1560s, before modernism and rationalism took over European thought (think Descartes, Spinoza and Leibniz). These confessions are warm, personal and relational (think Lord's Day 1).
James Arminius was a rationalist and hence came into trouble with the Reformed view of election. It did not work for him to say that, when it comes to the salvation of man, on the one hand, God is absolutely sovereign in choosing whom he would choose and, on the other hand, man is fully responsible in heeding the call to repent and believe. Ask the BC or the HC how a person is saved and there are two completely true answers: because of God's eternal election; because of man's faith, repentance and obedience.
This did not work for James Arminius; hence he developed his rationalist "election based upon foreseen faith" theory. Arminius was a pure modernist.
The Canons of Dort are the Reformed church's pre-modern response to a modernist error. They teach both man's full responsibility and God's absolute sovereignty without trying to "resolve the problem." Of course there is no problem. God knows how it works.
Abraham Kuyper and friends tried to "resolve the problem" with the doctrine of baptism on the basis of presumed regeneration. The theology that says God has his covenant only with the elect is also a modernist and a rationalist attempt to "solve the problem."
Yes, I'm thankful for my pre-modern confessional documents. As I find out every year when I teach the covenant youth of the church and others new to the church, our pre-modern confessional documents work really well in a post-modern culture.