Danmar
Thinks s/he gets paid by the post
I don't know that it is really that big a deal to keep things 'apples to apples' in this case.
Consider someone with a $1,200,000 portfolio invested 75/25 and a $200,000 mortgage, versus taking that down to a $1,000,000 portfolio and paying down the mortgage. AA choices like 75/25, or 60/40 or 50/50 are just round number targets. Would that person really adjust their AA after paying down the mortgage (or vice-versa)?
I just don't think it is a material enough change to make adjustments one way or the other.
I also sort of disagree that just because the payoff is considered a 'safe' investment, that one should adjust in turn. OK, it is 'safe' - but was the investor looking for that safety, or is it just a side effect of the nature of the payoff? In the big picture, I think it sort of washes out.
For an analogy, consider the decision between purchasing an annuity or not. We don't say that to keep it 'apples to apples' that one must consider an alternate investment that returns the exact same $ amount each year. No, we consider whether a portfolio can be reasonably expected to outperform an annuity in the long run, with ups and downs.
-ERD50
I agree. My basic point is that having a mortgage increases your risk. As long as this is understood and the effect is manageable no problem. It still is a little misleading to say "I expect to make 8% on my portfolio and my mortgage only costs 4% so it's a no brainer".
Not sure your analogy re annuities is valid. Annuities are really longevity insurance.