There is something about teaching that makes you a better researcher. I know this is very countercultural wisdom, but I believed it all along. Luria, Magasanik, and Levinthal all believed it. Levinthal and Luria both had a very strong influence on me in this regard.
An (old) interview with David Botstein, in PloS genetics. Link
At least we are spared the ‘research led teaching’ mission statements.