Don't move your pyrex jug filled with boiled dme straight from the gas stove to the sink filled with cold water.
Really? I've done this hundreds and hundreds of times. It's my standard procedure to take it right from the stove to a sink filled with cold water.
I am using real heavy duty Pyrex brand Erlenmeyer's though. Not the cheap shat all the HBS sell. Got mine from a lab supply store.