Apart from aesthetic preferences, replacing "loose weight" with "continually increase my fitness" (which is not something you'll ever be done with) is a far more constructive goal (and it will eliminate the diet-mindset-rollercoaster).
I suspect that lack of will power often means impatience. And impatience comes from unrealistic expectations regarding what you "should" be able to do in time n.
Daily moderate (will-power-) exercise will give positive results on a whole range of parameters, but it might take a year before the effects (including the habit of exercising) really show.
Off course you could be an exception.
"exercise that grows your muscle mass would do nothing for mine."
Bullshit.
The rational thing to do here is to replace 'goal: loose weigth' with 'goal: become fit'. Lift weights or do bodyweight-exercises (pushups, lunges etc.) + walk/run/bike.
"I often wonder what would happen if a Jezebel blogger stumbled upon this place."
What would happen and why should we care?