However, this strategy can probably can be employed rationally at certain times when the market were obviously undervalued (1997/98, 2008/2009) or when it was highly overvalued (bubble in 1996/97).
Therefore, in the long investment period that you are in, it is the rare occasions when you will be fully invested (80% equity:20% cash) or fully out of (50% equity: 50% cash) the market. (My own asset allocation figures ).
Did you feel that the market was a bubble in 2008?
Wealth Maximising Strategies for your Portfolio
Investment Strategies and Theories You Must Know for Greater Investment Success!