I think your critique of my simplistic example is valid, and suggest looking at the tutorial mentioned at the end of this node for a better demonstration of specification based testing. My point was using tcon->label() in a hackish way to find a distribution. Please file my ramblings under TIMTOWTDI :)
On reflection, maybe the point of Test::LectroTest is to try to expose the edge cases in your dependencies outside your own conditionals -- sqrt and division by zero come to mind. But I'd call it "stress testing" in that case and suggest that it is different from the way the term "testing" is usually meant in the various perl test suites. It doesn't tell you that your code is correct, only that it hasn't been shown to be incorrect for some number of trials.
I think that observation is correct. Specification based testing, which Test::LectroTest implements a framework for is based on the idea that you formulate the constraints. Then you leave it to the computer to try to violate your assumptions within the given constraints. This is one testing tool among many, and I find the technique useful, if only to allow myself to be humbled by my machine from time to time.
If you haven't seen tmoertel's (Test::LectroTest's author) excellent tutorial, I suggest taking a look. It demonstrates why manually testing edge cases in some cases is not enough.
Thank you for your comments!
Mischief. Mayhem. Soap.