System to overcome my MASSIVE late night tilt.

[kismet]

As I detailed in an earlier post my biggest leak comes in the form of burning off a ton of my winnings late in a session. I haven't isolated the cause of the blowup yet. I suspect a combination of better late night players, my concentration slipping, and a tendancy to start playing looser when I get a huge stack of chips. Early in sessions I feel good about my wins, as I scoop huge pots I should have never won just because I make great plays. I also "feel good" about my losses because I am focused well enough to realize that I did make a +EV play. Then there comes some point where I all of a sudden have half my hard earned stack left and have NO idea why. In an effort to recoup losses I think I blow the rest recklessly. So, as of late I have came up with a little fail-safe for myself, and I must say it is working great. I take my buyin and set a "win goal" around 3x what I started with. Once I hit my "win goal" I put into play my system for when to cash out. That system is to cash out if I lose more then %25 of my biggest stack. For example if I start with $30 I set my goal at $100. If I bust out I don't buy in and go home for the day. If I hit $100 then I put my cashout system into play. For $100 I'd cash out if I dipped to $75. As you can see this system allows me a chance to keep winning if conditions are good but puts a safeguard if they turn bad and I don't realize it. For example the other night I turned $0 into a $500 stack by winning the daily "freeroll" and going on a tear with the free chips. At $500 my cashout limit was $375, I think it kept me playing with more focus thinking I only had $125 to work with instead of the whole stack. There was also a mental plus in thinking I was leaving with $375 profit no matter what. I do understand I might be leaving when the table is profitable, but I am oviously lacking in judging this for myself. So I am kinda leaving the choice up to a system based on a math trick, until I feel comfortable making the choice for myself again. I am putting this in writing to make it more concrete, but I would also appriciate any opinions. Any similar systems that you guys use would also be great to hear about!