I think its a brilliant strategy for getting the marketable first novel done.
Look at the data... you're always dreading working on the large platonic NOVEL that your 11 year old plutonian nemisis signed you up for and decided could never happen.
By starting a novel that could potentially take you a decade or two to complete, it gives you a new move in the repetoire which is that when the GREAT swiss american novel gets in a rut, you can go play around by banging off a simply naratted, sympathtically protagonized, broadly accessible, plausible fable.
or more simply put, BEFORE as long as you feltlike you SHOULD be working on the novel, short stories were easy.
NOW that you've started a REALLY BIG novel to fret over not wanting to work on you might be able to trick yourself into feeling like a smaller novel would be easy.
And, even better than that, if this excercise in bad faith fails to be the foma that makes the difference you'll end up with Resilience in the can and the monkey off your back.