Limits can be a good thing creatively speaking.
For training purposes perhaps, but anything beyond that is a cop-out; trying to make some external process accomplish something that needs to happen internally. Downgrading from a Canon 1D-MkII and bag of L glass to an Olympus SP-350 didn't make me a better photographer while I was in Iraq; it was a constant nuisance dealing with the limitations of the tool, and I missed a few shots I'd have had no problem getting with the DSLR. Now that I'm back from Iraq, the Olympus is collecting dust until the next time I'm forced by circumstances to leave the DSLRs behind.