How Much Guilt Is Doom Capable Of Feeling?

Random comic-related hypothetical for the day: Would Dr. Doom be affected by Ghost Rider's Penance Stare?

(Setting aside the obvious answer of, "yes if the plot requires it.")

The Penance Stare inflicts upon the victim's soul all the suffering and anguish they have caused others. Which means it's proven ineffective against people who don't have souls. As far as I know, Doom still has his. I can't picture him being so desperate or foolish as to barter it to Mephisto or whoever. He'd figure he could deal with whatever problem he faced, so no need to resort to such measures.

But the Stare has also proven ineffective if the person you use it on doesn't feel any regret for their past actions. In the one example of that I've seen, it was because the guy believed all the pain he'd inflicted was for a righteous cause - punishing sinners - and so their suffering meant nothing to him. Which suggests Frank Castle would also be immune, but that's for another day.

So given that, it boils down to whether Doom has regrets over his past actions, and whether it's enough to drive him to his knees*. Offhand, I think Doom would certainly fall into the category of someone who believes all his actions are just. But he's also capable of feeling pain and sorrow, in his own melodramatic way. So I think it would hurt him, if it was the suffering of people harmed by his failures.

The times Doom challenged someone by himself because he was certain he could win, but he blew it, and others paid the price. The times his plans backfired and brought more trouble than he expected. Not because I think Doom cares all that much about the ones hurt as people, but it reflects poorly on him. Tarnishes that self-image he tries to project of his infallibility. Doom could deny the pain of people he chose to harm as having brought it on themselves for challenging him, but the pain of those hurt because he wasn't up to the challenge might be a different matter.

* The Doom that played at being Iron Man a couple of years ago definitely does, and barring him using some spell to protect himself, would absolutely be vulnerable.