OK, I see where you are coming from now (I think). So sure, equity in a house is certainly worth something. I don't think anyone is denying that. A retiree with $X portfolio and some home equity is certainly in better shape than a retiree with the same $X and *no* home equity.
But what some of us are saying is: Assume that your home represents some standard of living that you wish to maintain during your retirement.
and what i said is that your home has a certian portfolio value which i will now call $Y (since you just used $X as the rest of the portfolio) which is computed more like a landlord would compute the present value of his income stream from that house if it was rented. and in other words $Y would be the retirement $ value of that standard of living you mentioned
At that point, the $ value of it does not mean much. It is what it is, also assuming that any future moves would be a "sideways" move in cost (maybe trading square foot for location or other qualities, but at roughly the same cost). So, whether it goes up, down, or stays flat in value is of little consequence - it's all a wash.
since we now have 2, potentially different, values for said house (what i call $Y above and the price you could get for the house if you sold it, lets call this $Z) i must disagree with you when you say that "it does not mean much" and that "it's all a wash". it is only a wash if $Y = $Z
Under those assumptions, let's say my home quadruples in value (along with all comparable properties). I am not in a position to increase my spending based on this higher Net Worth, because I didn't really "gain" anything - replacement homes are the same cost, and I said I was not going to downgrade. So why include it in a Net Worth calculation?
-ERD50
ok lets consider that. first lets set the initial conditions, you own the house F&C and before the increase in value $Y = $Z. now when you say "my home quadruples in value" i am assuming you are talking about $Z quadruples in value, but if $Y doesnt quadruple in value then you could harvest some of the $Z's increase and not affect your standard of living. that amount would be $Z - $Y. you could do that by selling and moving into a rental.
there is a similar argument for moving to a different part of the country (or world for that matter) however this kind of move has other factors involved that might outweigh the financial side.