This is how you end up living off of cat food from sequence of returns risk.
Unless you're willing to drop your savings rate significantly during a pullback? But then you have to ask yourself, "is this part of my plan?"
Yeah and I don't think I'd want to do that (i.e., eat cat food. Heck the cat doesn't even like it much!), so I'm letting it ride. I just got my "plan" from Vanguard (just switched the stash from Personal Capital) and they say my scenario has a 99% chance of success until I'm 100. So, if it looks like my stash doubles or triples (as the chances are good that will happen, or better) I'll adjust then. However, in my first few years of FIRE I plan on adding to the stash when possible, keeping expenses in check, and sticking to the 4% SWR.
I recently listened to a financial podcast (probably on the Mad Fientist). Some financial expert said that this could be done. He sometimes let his clients take out 5%, instead of 4%. Similarly, you could reduce your 4% a bit in big downtimes.
I advice you to find back this podcast. I don't remember who said it.
I'd like to listen to that.
As far as adjusting up or down depending on the year, I might find that stressful so I'll try and live within my means for now.
It is still tempting though, given the great returns has year, and my VG forecast for such a high success rate to 2061 (which is still five years short of my planned expiration date :).