I am a former NASA robotics scientist, degreed in Applied mathematics, Aerospace Engineering, Mechanical engineering, (and a few other degrees not relevant in this case). this doesn't mean that I am automatically right and you are wrong.

My question to Mike is purely mathematical: how much market must loose in order for me to start losing money from my paycheck?

You are the one failing to supply the mathematical calculations of how you plan to replace $8,000 a month in appreciation. 

My feeling is that if a finance whiz did a mathematical model on these approaches you would come out ahead focusing on one specific property at a time for early paydown but I am not that whiz so I won't undertake to prove it with math.  

Being able to mathematically add value with commercial property by increasing the NOI is a great strategy for wealth building.

Mathematically, one option is slower growth (which you agree to).

When you buy stocks, you're setting your intuition and understanding of the marketplace against professionals, guys attacking the prediction of stock prices using advanced mathematics and modeling.

But we are all out our opinions, no matter what laws of nature or mathematics they violate :-)It sounds like you can distance yourself from the sales and mentoring aspect of the presentation, and that is very good.

(THIS IS THE SECOND EXAMPLE ABOVE THAT YOU CLAIMED COULDN'T MATHEMATICALLY EXIST).As you can see, the negative leverage (extreme negative leverage in this case) reduces your NOI and your COC by 50%. 

Short term LUCK can prevail; over a longer term the mathematical “odds” begin to dominate the equation.So, how does an investor learn to “perceive” risk \ reward more accurately than the general public, and hence increase their odds of obtaining greater returns and/or less risk?