The way I understand it, with these LS engines, is that they regen every 50hrs. Mine did, exactly at 50hrs. 26hrs over 9 months is not a ton of use, but for a home owner that only needs it to plow snow or move somethign heavy, odds and ends, that sorta thing, its not out-of-this-world low. The button is to by-pass the regen. So if you are out in a wheat field or something that you really dont want to burn down, you can by-pass it temporarily to avoid burning down your field type of thing. It shouldnt be used all the time and the regen should take place very shortly after. It is just to get you to a safe place before turning your exhaust pipe red.
I believe, but not certain, that you can also initiate a regen by using this button too. Not sure about that.
My tractor currently has about 80hrs on it, bought it this last April. It has regend once. It notified me and I did what my dealer told me to do, which was firewall the throttle and lift the bucket out of the way to prevent the paint from burning. About 10 or so minutes later, and after some odd burning smells, it was done. I throttled back and went about my day. They say you dont need to stop working, but I did, just to watch it happen.
I dont believe Rusty's issue was due to a lack of regen or the DPF being an issue. Might have, but probably not.
Just my .02