Nowhere is it guaranteed that, given the cognitive architecture humans have to work with, epistemic rationality is the easiest instrumentally rational manner to achieve a given goal.

But, personally, I'm still holding out for a way to get from the former to the latter without irrevocable compromises.

It's easier than you think, in one sense. The part of you that worries about that stuff is significantly separate from -- and to some extent independent of -- the part of you that actually makes you do things. It doesn't matter whether "you" are only 20% certain about the result as long as you convince the doing part that you're 100% certain you're going to be doing it.

Doing that merely requires that you 1) actually communicate with the doing part (often a non-trivial learning process for intellectuals such as ourselves), and 2) actually take the time to do the relevant process(es) each time it's relevant, rather than skipping it because "you already know".

Number 2, unfortunately, means that akrasia is quasi-recursive. It's not enough to have a procedure for overcoming it, you must also overcome your inertia against applying that procedure on a regular basis. (Or at least, I have not yet discovered any second-order techniques to get myself or anyone else to consistently apply the first-order techniques... but hmmm... what if I applied a first-order technique to the second-order domain? Hmm.... must conduct experiments...)