Yep. I have already stipulated that there is no intention to give your incontestable proof. But those eyewitness accounts have been enough for a billion or so people already.
I agree that the Flood would certainly leave a mark ...if God wanted it to. But since it was clearly a supernatural event (where did all that extra water come from anyway?), it is just as likely that the scientific proof disappeared with the excess water.
It's a delicate balancing act... leaving just enough evidence to satisfy those who are looking for Him but not enough for those who require iron clad proof.
Those who require iron clad proof require said proof because they are looking for him. They just don't want to make a mistake. Examining facts before claiming something is true is what advanced science to where it is today.
The best way of thinking of this is your doctor says you have an infection and need a shot of antibiotics or you'll die. It's a good idea, maybe, to get a second opinion but holding out for iron clad proof is a good way to end up dead.
The difference is that doctors usually have a history of being correct in their diagnoses and there's plenty of scientific proof showing that antibiotics will help get rid of the infection. There's nothing like that when it comes to christianity.
Actually, no. George Washington died because his doctors bled him to death with leeches. The history of medicine is much worse than the history of Christianity. You pick a doctor carefully, you should pick a pastor carefully. Both can do you a lot of good or a lot of harm.
But you missed my point. In the case of your particular chosen doctor, you rely on the fact that he has studied hard and trained well and therefore your decision to accept what he prescribes does not involve going back and reviewing whether there is absolute proof available. You don't demand such evidence to save your physical life, why do you demand it to save your eternal life?