texmath-0.6.7: tests/writers/munder-02.tex
\underset{\mathrm{under\ script}}{\mathrm{BASE}}=\underset{\phantom{\mathrm{fail}}}{\underset{\phantom{\mathrm{fail}}}{\underset{\mathrm{under\ script}}{\mathrm{BASE}}}}\underset{\mathrm{under\ script}}{\mathrm{BASE}}=\underset{\phantom{\mathrm{fail}}}{\underset{\phantom{\mathrm{fail}}}{\underset{\mathrm{under\ script}}{\mathrm{BASE}}}}