Sure, avoiding information is an example of patching a decision theory, agreed.

So I guess what I'm saying is that "either eliminate the information, or fix the decision theory" is a misleading way to phrase the choice. My real choice is between fixing it and patching it, where eliminating the information is one of several ways to patch it, and not always the best.

Making choices about future investments in ignorance of the existing data I have about previous investments and their ROI is probably less ideal than taking those data into consideration and applying some other patch to compensate for sunk-costing.