I've had to do this a couple of times with high gravity, vigorous fermentations. Never had a problem with it clogging, but the krausen will definitely push through into the tubing and that is not fun to clean in the slightest. There are also a few LHBS's that sell short bits of rigid tubing (3/8" OD I think) that fit snugly in the stopper and tubing so you don't have to worry about scrubbing out the hard to reach parts of your airlock. Using these require prior planning on the expectation that you're going to get an overflow to begin with though.
California Pale Ale
Rye IPA, Citra Pale Ale, ESB, CO Pale/Simcoe SMaSH
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