When they heard these things, they became furious and ground their teeth at him. But Stephen, full of the Holy Spirit, looked intently toward heaven and saw the glory of God, and Jesus standing at the right hand of God. “Look!” he said. “I see the heavens opened, and the Son of Man standing at the right hand of God!” But they covered their ears, shouting out with a loud voice, and rushed at him with one intent. When they had driven him out of the city, they began to stone him, and the witnesses laid their cloaks at the feet of a young man named Saul. They continued to stone Stephen while he prayed, “Lord Jesus, receive my spirit!” Then he fell to his knees and cried out with a loud voice, “Lord, do not hold this sin against them!” When he had said this, he died. - Acts 7:54-60 (NET)What he does address is that when we "pray in the name of Jesus," we are going to the Father by the authority Jesus has given us through the power of the Holy Spirit. Koukl references Hebrews 10 with regards to the interworkings of the Trinity. Here is an excerpt:
By his will we have been made holy through the offering of the body of Jesus Christ once for all. And every priest stands day after day serving and offering the same sacrifices again and again—sacrifices that can never take away sins. But when this priest had offered one sacrifice for sins for all time, he sat down at the right hand of God, where he is now waiting until his enemies are made a footstool for his feet. For by one offering he has perfected for all time those who are made holy. And the Holy Spirit also witnesses to us, for after saying, “This is the covenant that I will establish with them after those days, says the Lord. I will put my laws on their hearts and I will inscribe them on their minds,” then he says, “Their sins and their lawless deeds I will remember no longer.” - Hebrews 10:10-17 (NET)I think that, regardless of any debate on this topic, the important point to note is that Christians should become more aware of their theology and just how it affects their Christian walk. One of Wendy's comments sums it up nicely:
I believe that Christians should pray with purpose and intent, and knowing each Person in the Trinity is unique is what leads me to address a certain Person within the Trinity depending on what I am praying for.Update: I was scanning the Heidelberg Catechism and found that questions 119 and 120 related to this topic.
119. Q. What is the Lord's prayer? A. Our Father who art in heaven, Hallowed be Thy Name. Thy kingdom come, Thy will be done, On earth as it is in heaven. Give us this day our daily bread; And forgive us our debts, As we also have forgiven our debtors; And lead us not into temptation, But deliver us from the evil one. For Thine is the kingdom, and the power, and the glory, for ever. Amen.  Matt. 6:9-13; Luke 11:2-4. 120. Q. Why has Christ commanded us to address God as Our Father? A. To awaken in us at the very beginning of our prayer that childlike reverence and trust toward God which should be basic to our prayer: God has become our Father through Christ and will much less deny us what we ask of Him in faith than our fathers would refuse us earthly things.  Matt. 7:9-11; Luke 11:11-13.