Kinda late in the game here... but I've seen this argument come up a lot recently, and it's incredibly odd to me.
There will never be the possibility of proving either position (Creation or Evolution) because of the fact that origins happened in the past and cannot be revisited in any real concrete fashion. It will forever remain in the past and be something we can only hypothesize about.
How far back do you apply that alleged inability to understand the past?
If you happen upon a tree in the forest, uprooted and laying on the ground, do you assert that we can never know what happened to that tree? Do you assume the tree just appeared on the earth in the exact position it is currently in? What if further analysis determined the tree had been dead for a while, and damage to the roots indicated some kind of insect infestation that weakened its base?
What if all the evidence pointed to a particular conclusion? Would you dismiss that conclusion simply because whatever happened must have happened in the past?
If so... how far back do you draw the line of our inability to understand the past, and what criteria do you use to make that determination?
Here's another example... let's say the area currently known as Yellowstone National Park had never been discovered. 50 years from now, we finally find it and see the areas that had previously been destroyed by forest fires, and some that had since regrown.
Are you saying that we are unable to apply our current understanding of forest fires and biology to those areas to explain why there is this otherwise-unexplained burned section of forest?