[Aquinasfan]

Irrationality is "I have two [or more] courses of action, A and B. In my opinion, B is better than A, therefore I will do A"].

That's true, but you're missing a crucial point. Suppose that I have two courses of action before me, binge drinking and moderation in drinking. I know that it's better for my overall health to drink in moderation. But instead, because I so love the pleasure of drinking, I choose to drink myself to death. In this case, I am choosing the apparent good over the objective good.

No one chooses against what he perceives as good, but this does not mean that he is acting rationally, since he is acting against right reason.

The Goodness and Malice of the Internal Act of the Will

[GSlob]

There is no apparent vs. objective good in your example. In your example your love of "pleasure of drinking" pushes the binge drinking value [for you] into the designation of 'greater good". So, naturally, and pretty logically, you choose the greater good over the lesser one. In your value system, however deranged it could be or appear, you will always be entirely logical- you have evolved that way. The only exceptions are accidents, and one could even make the same argument about the involuntary actions [I force you to drink at gunpoint. You do not want or like to drink, but you do not want to die either - and naturally and logically, you choose the lesser evil, aka the greater good, and drink].
And as for your other post - yep, I saw the pictures. No emotional reaction of any significance on my part.