I ask this question because looking long term there must be some danger signals that are clear to those with the wherewithal to take notice, to me, not acting seem like setting your self up for a more wide ride than necessary.
Is there any P/E or related metric level at which you would change your asset allocation?
Lets say, like some of you, a mustachian is looking at a 40 year investing career. Given this - this mustachian is 100% long on stocks- say VSTAX - would it make sense to have some thresholds at which to move to bonds, cash, or other asset classes based on market performance?
For example, an trigger at a P/E of 30- move to 50% cash, a trigger of P/E 20- back to 100% stocks?
cheers