Etex recommends 2 minutes of VIGOROUS mixing with its instructions. therefore, if you wish to split hairs, one minute of even vigorous mixing is probably insufficient. Note that I used the word 'probably' in my response, because when mixing for lure building a lot of guys do not like to mix the stuff too vigorously because it creates more micro bubbles in the stuff. Thus usually with less than "vigorous" mixing, at least 3 to 4 minutes would PROBABLY be in order.
Also kindly note that from what I read above, the author of the thread went back with apparently the same batch, mixed it longer and voila, problem solved.
Lastly, I'm not sure how one would describe etex as "forgiving." Fail to mix it properly or fail to mix it 50/50 and it will do anything but forgive you.
Sagging, fisheyes, a somewhat electrostatic dust-attracting charge when you first mix it (which tends to dissipate if you let is sit for about 10 minutes before application), and the need to torch the stuff to remove bubbles are among a number of the ways it could hardly be described as "forgiving".... and this board has a zillion questions about those problems to prove it.