Thanks for the info, reeshau and MustacheAndaHalf, that is the kind of thing I was looking for. The person pushing this actually wants to use it as part of a short term timing strategy, where stop-loss orders kick in on the index funds if that index drops by X%, then buys take place if it goes back up by Y%, for each fund, including these, so I think we would be swapping between these and "normal" index funds as the market fluctuates. He has a model he has been back testing against the market to show that it produces above market returns. Originally this model showed something like double market returns for the last 10 years, and I politely expressed my skepticism that if such a simple model worked, all of Wall Street would be using it, then he found a mistake in his spreadsheet which removed most of the excess returns, though it was still maybe 30% over the market for the decade. He then bought access to more detailed data for the last 10 years, but that crashed his spreadsheet, so he is now writing a program to do the back testing calculations to set the X and Y percentages for optimal returns.
Meanwhile the groups original stop-loss kicked in when the market dropped back in March, and they have sat 100% in cash (money markets and bank accounts) since then because we don't yet have a plan for where to put stop-loss orders in. There is universal agreement that stop loss orders must be in place, as we can't afford to lose money, and I'd rather have the investments at least 65% in stocks with a mechanical stop-loss/repurchase system in place than leave almost everything in cash equivalents, as was done previously. While I strongly suspect the stop-loss/repurchase system will cut returns somewhat compared to buy and hold, I don't think it will cut returns as much as not being in the market at all, since trading costs are pretty low these days.
Could be worse, one person who was on the committee would have preferred something like 50% gold/50% insured bank accounts, and quit in protest at the insanity of risking any money in the stock market.