There aren't a whole lot of studies that really support that theory (if any) that I've seen.
Im just basing that off of personal experience.
I did 1600 cals, got ripped and slowly got fatter and less cut even staying at or around that that level for months after. I held the condition for about 4 - 6 weeks before it went south.
Also when dieting that low, cheats become more normal and "acceptable".
My goal is this year is sustainability and being able to STaY lean without crash dieting, and the use of mimimal drugs. Anyone with wilpower can crash and get lean...but staying lean is the hard part