Buffett on the market valuation

As stated in the GuruFocus' "Where are We With Market Valuations?" article, "as pointed by Warren Buffett, the percentage of total market cap (TMC) relative to the US GNP is “probably the best single measure of where valuations stand at any given moment.”

What were his comments in a December 2001 Fortune article about the market in 2000?
Memorably he stated that "the ratio rose to an unprecedented level. That should have been a very strong warning signal."

[It reached 148.50 on 3/30/00]

What was the percent return of the S&P 500 after the Market Cap/GDP reached that "unprecedented level?"

[it dropped 43.1% in three years]

Has there ever been another time when Buffett touted a “very low-cost index?”
As stated on Reuters.com in the Buffett: Index funds better for most investors article by Jonathan Stempel dated May 6, 2007, “Buffett said at a press conference,” “A very low-cost index is going to beat a majority of the amateur-managed money or professionally-managed money.”

What was the Market Cap to GDP at that time?

[110.70 on 6/30/07]

What was the percent return of a “low cost” ETF that tracks the S&P 500 from May 6, 2007 to March 2009?

[it lost 53.6%]

What is the Market cap to GDP today?

122.3%

Considering the "best indicator where valuations stand," is currently near previous highs, might Warren actually be estimating that by the time his trustee is needed, the Market Cap to GDP will be at much lower levels?

If the valuation ratio reverts to those historical lows of 40%, and we are currently at 122%, does that mean a near 67% drop is possible?