User blog comment:B1mb0w/Strong D Function Calculations/@comment-1605058-20150701125933/@comment-10262436-20150701135110

...I have no idea how you get from n\uparrow\uparrow n to \varepsilon_0. You need much more than n.n\uparrow\uparrow n iterations of, say, f_\omega(n), in order to get to f_{\varepsilon_0}(n)...

just quickly. I am not arguing that. I am saying. You n.n\uparrow\uparrow n iterations of D(2,0,x) to get to f_{\varepsilon_0}(n)...