Constant awareness of the Eintstellung Effect would make a useful addition to our cognitive toolkit.
The Einstellung Effect is more ubiquitous than its name suggests. We constantly experience it when trying to solve a problem by pursuing solutions that have worked for us in the past - instead of evaluating and addressing it on its own terms. Thus, while we may eventually solve the problem, we may also be wasting an opportunity to so in a more rapid, effective, and resourceful manner.
Think of a chess match. If you are a chess master with a deep familarity with chess history, you are likely to spot game developments that look similar to other matches that you know by heart. Knowing how those previous matches unfolded, you may automatically pursue similar solutions.
This may be the right thing to do in matches that are exactly alike - but in all other situations, you've got to watch out! Familar solutions may not be optima. Some recent research into the occurences of the Einstellung Effect in chess players suggests that it tends to be less prominent once players reach a certain level of mastery, getting a better grasp of the risks associated with pursuing solutions that look familiar and trying to avoid acting on "autopilot".
The irony here is that the more expansive our cognitive toolkit, the more likely we are to fall back on solutions and approaches that have worked in the past instead of asking whether the problem in front of us is fundamentally different from anything else we have dealt with in the past. A cognitive toolkit that has no built-in awareness of the Einstellung Effect seems somewhat defective to me.