Itīs just as viable as sniping Protoss Pylons or hit-and-run against Terrans untill their Buildings are in the Red.
Itīs less a crippling Zergweakness but more a precaution against Creepdrop->Techbuilding->stop Creepdrop. Zerg benefit from hidden Tech the most, itīs just fair that Creep gives them away.