I believe that the claim that Jesus is God is overt in the Gospels, but that we don't see it because we don't look at the Gospels as a Jew in the first century would have.
One of the ways in which the authors of scripture tell us that Jesus is God is through an overt reference to the very first verses of the Hebrew Scriptures.
**In the beginning, when God created the heavens and the earth, the earth was a formless wasteland, and darkness covered the abyss, while a mighty wind swept over the waters. (Genesis 1:1-2)
He woke up, rebuked the wind, and said to the sea, “Quiet! Be still!” The wind ceased and there was great calm. Then he asked them, “Why are you terrified? Do you not yet have faith?” They were filled with great awe and said to one another, “Who then is this whom even wind and sea obey?” (Mark 4:39-41)*
In Genesis 1, God creates Heaven and earth, and in so doing, wields absolute power over wind and water. I believe that Mark's placement of Jesus in a power of absolute authority over wind and sea was overt, and that Jews who were knowledgeable about the Hebrew scriptures would have recognized the reference. I believe that this passage, and parallel passages in the other Gospels, were clear statements of Jesus divinity - that he was the same God who created Heaven and earth in the book of Genesis.
Mark and the other Gospel authors use similar techniques, references to Genesis and God's power to create, to tell their audiences that Jesus is in fact God.
**Then he said to them, “The sabbath was made for man, not man for the sabbath. That is why the Son of Man is lord even of the sabbath.”* (Mark 2:27:28)*
The sabbath was of divine origin, created by God on the seventh day when God rested, and given by God as a gift to mankind. To claim that you were "lord of the sabbath" was to claim that you were the creator of the sabbath, and that you had authority over the sabbath. Again, the Jews would have recognized this as a clear indication that Jesus claimed to be the same God who created the Sabbath for man in Genesis 2:1-3.
Similarly, Jesus' cleansing of the temple in Mark 11:17 was a sign that he had authority over the temple. Jesus claim that "Something greater than the temple is here" in Matthew 12:6 would have been especially shocking. To a Jew in the first century, the Temple was the center of the universe, where God dwelt with men, and to say that you were greater than the temple was to claim that you were God.
This is why the chief priests and scribes sought to kill Jesus for blasphemy, because to a Jew, these were clear claims by Jesus that he was divine, that he was in fact the same God (consubstantial?) who created Heaven and earth, the sabbath, and the temple.