Scantee, I think your fears of stagnation are potentially overblown. Are you concerned about worldwide stagnation? I personally don't see how the entire world market can stagnate for longer than a few years. People simply still create and buy things. If you are internationally diversified, I don't see the concern.
I concur with others saying that I'd welcome a crash right now. In my retirement timetable, it would mean I could buy some more or maybe a house. My only concern would be another long bull after that may have me worrying about a crash as I start retirement and getting into some sequence of returns risk. Ideally I'd retire about 1-2 years after a crash, heading into a bull. But the 4% rule pretty much just means don't retire right before the great depression and you are fine.
Over the long-term, no, I don't think worldwide stagnation is an issue. But even 3 years of stagnation like we had in the 70's would really mess with the plans of people, like me, who want to retire during that time.
I'm pretty wary of welcoming another crash. My biggest takeaway from 2008 is not that a crash is a great time to buy (I already knew that). It's that not only can you not call
when an economic downturn will happen, you also can't anticipate
why it will happen or
what it will look like. If we could anticipate what it would look like, it probably wouldn't happen! Almost certainly the next downturn won't look like what happened in 2008, so if your ER plans involve looking forward to or counting on an event like that happening, you're probably planning on the wrong thing.
So I'm not holding out any hope for buying "on the cheap". I'll continue on my current path and do what I've always done, which is to follow the advice of MMM and other sage buy and holders:
1) Dollar cost average,
2) the maximum amount I can invest,
3) following the set allocation I'm comfortable with, and
4) stick to it regardless of external circumstances.