Personally, JP states that high yield stocks (above 10% or so) are risky.  So, in order to get an expected return above that, he adds the current dividend yield to the expected dividend growth rate.  I, personally, consider that a riskier strategy.

For example, a stock I own (Frontline Tankers FRO) has a current yield of 11%.  Josh would not include it in his portfolio for a few reasons.  First, it has too high a yield.  Secondly, it's dividend growth rate is sporadic (depends on tanker oil transport spot rates).  Third, it's a relatively small company that hasn't been around long.  Fourth, it has no moat.  Fifth, it's ROE is quite high and might not be sustainable (55%).  And so forth.

He would choose instead a stock with a 6% yield and a 5% dividend growth rate.

I would consider FRO to have an expected return of 11% (ignoring any dividend and share price growth).  Josh would consider his company to have an 11% expected return also, and would include it in either of his portfolios.

The difference between FRO and Josh's company is that he's betting on the come (5% dividend growth rate, going forward), while I'm betting on the excess 5% of current yield FRO is generating to be sustained, going forward.  FRO's growth will come from compounding the excess 5% yield it's generating.