I can already see a dozen things going wrong (where is your tape measure b.t.w. I know I would forget to use one but that's then 13 things gone wrong). I can also see that your amazing ingenuity would have taken me two days and as many fridge doors!
And yeah, you gotta love Ikea (even after watching Fight Club)....
I only use tape measures when I absolutely have to. Otherwise I just go by the look of it! ;)
I love both Ikea AND Fight Club, it's one of my top 5 movies! :)