I think to be fair (and maybe just to feed your curiousity), you deserve to know what gave you away. Of course, I'm telling you this hoping you understand that you really, really don't have to jump from handle to handle. I'm glad you recanted, 'cause it'd be a shame to let the progress and reference in your alter-egos' various projects go by the wayside. You see why you can't do this? You'd spend so much energy trying to be someone you're not that you wouldn't have any energy left to be anybody at all!
Anyway, let's look at the clues:
1. The Handle. All began with capital letters, with more similarity between the first two handles than with Krumlink, although this may be in part due to the inherent shortness of the last handle. Krumlink is obviously a name you've chosen either consciously or subconsciously based on your frustrations with the forum in your other two incarnations.
2. The Avatar. There's a link of military-themed avatars, and while this isn't the case for Robot builder, the military connection was evident by way of the tank included on your short-lived website (incidentally, bring the website back, but with more content than fishing for freebies). Also, Robot builder and Souperman included avatars with faces, which suggests a self-awareness and perhaps even narcissism.
3. The Signature. No doubt missing in the second handle to distance yourself from the criticism drawn by Souperman's gratuitous signature. It's made a comeback with Krumlink (let's hope it stays to only a couple lines!), but there are also other similarities: the use of the imperative, and referencing other threads on the forum.
4. The Location. Already mentioned, and I would've thought the easiest to fake, so I can't figure out why you didn't.
5. The Rebuttals. I can't quite nail it down, but for some reason the rebuttals (your alter-egos' posts in reference to each other) were the thing that gelled it all more than anything else. It was just too introverted to be realistic, I guess, and anyone who's tried to write a piece of fiction knows how hard it is to write for two different characters.
6. The Join Dates. The actiivity of a new handle and consequent inactivity of an old handle was a dead give-away. You tried to mask it with the rebuttals, but let's face it, how long could anyone keep that up?
7. The Content. Who involves himself in a forum to talk about anything other than the things they're most interested in? Trouble is, most people aren't interested in very much - they have their thing and they stick to it. You can't hide from that kind of personality.
8. The Repeat. What's the best way to catch a killer? Get him to kill again.
Welcome to the forum, Rob Linkman.