Fair enough criticism. I was trying to make the point that various backtest starting points will produce quite different results. I am actually not much of a fan of backtesting, particularly for things like comparing sectors, because sectors are constantly changing relative to one another. Using history with international stocks feels particularly uncertain to me, with the rise of China, the turmoil of the BRICS countries, and the waxing and wanting of the EEC --- all much more recently than 32 years.
And note that probably no one's long term investing strategy involves buying on day one and sitting for 32 years. Either one is accumulating or one is spending down. So that kind of backtest isn't very real world.
So, I"m still in the "buy everything" camp; backtesting over 90 years or more that strategy seems to have held up. Beyond that, I am firmly in the "clueless" camp on what will happen next.