It matters a little no? Every pay check you take out is a bigger percentage of the whole while the market is down, and when it inevitably rebound, you have much less to grow back into.

With that said, while I make sure to have contingencies in the case I do end up living for longer than expected, given the average lifespan of an American and the a mid 60s retirement age, "living for 20-40 years after you retire" is not something everyone can count on.

The other poster has a valid point: as you get close to retirement you shouldn't own too much stocks, but then if the market crash around the time you start seriously converting to bonds and stuff, you have to delay that plan and manage things a lot more closely.

In theory, yes. In practice, many people will flinch and sell, maybe even near the bottom.

edit: (But also, you should probably not own a ton of stocks near your retirement date)