Get a belt before worrying about walkouts.
I have had great success with walkouts. My problems are generally psychological...I'm a wuss. I walkout about 30 to 50lb more than my worksets and once I'm done my worksets feel a shit-ton lighter. I only hold it for about 3 to 5 seconds though. And I wear my belt and brace like hell. I do not qtr squats with it or any of that bullshit...I think that would just reinforce bad form.
Another major help if problems are psychological is to squat in a power rack. With properly set satefies, you really can't screw up...even if you fall forward (which I've done), the safeties catch it and your fine. I only use spotters at meets, because I would worry I'd fuck up and hurt them. Can't hurt a power rack (just the bar I guess...but better than a person).
Also, I would force fail something, but once you gracefully set a heavy set on the pins, you realize...its really no big deal at all.
Meant to say, I would not force fail a heavy weight. But once you do...you realize no big thang.
Most of the pussies and fat acceptance crowd on the SS forum will tell you that partials, walkouts and that sort of thing is bad for you. So filter them out. But they probably are a little dangerous if you are stupid though.
In my anecdotal experience you can't do enough work on them to warrant any actual overtraining that would affect your regular training, but I haven't actually found them useful or helpful in any way either to helping a lift. It's something I might do on a 'day off' just cause I am bored but I wouldn't expect miracles. I think for your average trainee (or new father) your time would be better spent enjoying life, or doing some light conditioning if you are not doing work sets.