In some parishes Trinity Sunday was the time to give a financial report, anything rather than preach on the Most Holy Trinity. The problem is of course that too many Catholics think of the Trinity in terms of algebra or geometry rather than in terms of relationships.
Muslims love to debate with Christians God in terms of the 1+1+1=1 approach, they are less comfortable with the idea of the God who loves to point of emptying himself of His Divinity to embrace His creation, indeed to dwell within it and suffer with it.
The high point of our prayer is always the doxology, when we address the Father, through the Son, in the unity of the Holy Spirit. Indeed when we look at a crucifix we are supposed to, in a sense look through it to the Father, the high point of the Eucharistic prayer is the priest taking up the Sacred Host and addressing the Father saying, "Through him, with him, in him, in the unity of the Holy Spirit, all glory and honour is yours, almighty Father, for ever and ever. Amen."
Although popular devotion might address individual persons of the Trinity, the Church's liturgy, with a few notable exceptions is addressed to the Father, through the Son, in the Spirit.
The Son is perfect icon of the Father, in His humanity we see revelation of the Father. Perhaps the worst sermon I ever heard on the Trinity was basically, "The Trinity is a mystery we can't comprehend, so let us get on with the Mass!". It was the worst but yet it was also the best, because the Triune God is always mysterious and unknowable, and yet He is revealed totally in the Mass, through the Son, in the Spirit.
True worship always leads us to contemplate the God who is always beyond us, the God who in the Old Testament patriarchs and prophets fall on their faces and worship.
Practically at every Mass I have celebrated over the thirty years I have been ordained I have felt the need 'to break the bread of the word', to preach, except at the Traditional Mass, where all I want to do is adore the Father through the Son, in the unity of the Holy Spirit. I am beginning to believe that if the Word of God does not lead us to worship there is something wrong in its presentation, and if the Mass does not lead us to fall on our knees to be fed by God there is something wrong here too.
Contemplating the Mystery of the Trinity should lead us to be lost in the immensity and beauty of God, realising his greatness and our nothingness, desiring only to abandon ourselves to Him and crying out with Christ, "Father into your hands I commend Spirit".
If this realisation is not the result of worship, perhaps we are not worshipping at all!
Per ipsum, et cum ipso, et in ipso, est tibi Deo Patri omnipotenti, in unitate Spiritus Sancti, omnis honor et gloria per omnia saecula saeculorum. Amen