I haven't read Dan Brown-- so I cannot say one way or another.<quoted text>
Yes I know about the controversy in deciding whether Yeshua was human or divine. I do know that Constantine brought the two opposing sides to the table to decide, but I do not believe that he tried to directly influence the Council of Nicea. The evidence I've seen doesn't support that theory to the extent that sensationalist authors such as Dan Brown would have us believe.
But you are wrong on at least one point: the group had decided to put Revelations into the apochraphia[sp] group-- but Constantine required an exclusivity clause for his newly-minted religion, so he could justify forcing by violence people to join his new club.
It's on record that Constantine overrode the will of the group in that regard.
So I have no doubts at all, that he also used his force of personality, to override other decisions too.
It does appear Constantine suffered from a massive dose of hubris, after all.
And that rather puts a negative spin on the whole project.