I am a mathematician, not a programmer, but even I have a Lisp story like this. I'm working with a computer science professor at my university who has in the past worked as a programmer both for private companies and for our government. We're studying some combinatorial game played on graphs and wanted experimental data of which player has a winning strategy on thousands of small graphs.
To feel more certain of the computer results we decided to each write our own implementation independently without looking at each other's code. He wrote his in C and I wrote mine in Common Lisp. You can imagine the punchline since it is similar to all of the Lisp stories out there: my program is about a tenth of the number of lines of code, took much less time to write and runs about twice as fast!
Also, I'm skeptical about this scaling limit business, but if it's true, call the first program a prototype or proof of concept and then rewrite in a "scalable" language when necessary. "Plan to throw one away, you will anyway."