Becoming a Christian actually made me less likely to use Christian symbolism and structures in my work because now I see Christ's presence underlying all of life -- I don't have to place Him there artistically.
In this sense, Klavan seems to argue that Christian symbolism is life itself. Symbolism is typically used to suggest something that is on some level foreign to the setting of the work of art. For example, In Moby Dick the whale himself is symbolic of many things, not the least of which is the horribly sublime power of God. Melville uses the whiteness, among other things, to highlight this aspect of the whale's symbolism. The symbol here functions to allude to some quality that is not inherent in the natural image of a whale. But in light of Klavan's view of symbolism, there is no need for the artist to use any symbols at all to allude to God, since it is the very nature of His creation to allude to Him.
Calvin Seerveld bases his whole aesthetic upon allusiveness, which basically means that the core of art is that it alludes, and in the case of good Christian art it alludes to God. If Klavan is correct, then all a Christian artist needs to do in order to make an excellent work is to accurately portray their subjects. If they do this, then they will be alluding to God since His creation itself alludes to Him.
I'm going to have to consider this idea further before I can make a judgment, but one of my first reactions is concern since this idea seems to imply that the greatest form of Christian art is the realist work, which, to me, seems to stifle creativity and privilege skill. Let me know what you think.