What would you do if your goal were to be as mediocre as possible while still appearing reasonable to experienced investors?

I've been talking about this with friends and family as a fun little thought experiment and I wanted to get a 2nd opinion.

Imagine you have a supervisor named Mike, a CFA charterholder and professional investor with 20 years of experience who can obviously spot common mistakes rapidly.
Mike has advised you to write your own investment memo and he will come back every Quarter to revise both your individual stock picks (evaluating the businesses), your broader asset allocation (ETFs, commodities, bonds, etc) and your own research supporting each position.

Your goal is to be as mediocre an investor can be as possible while still fooling Mike into thinking you're doing fine while still actively sabotaging yourself in the long term, so how would you do so?