FYI...use at least one oz of whole hops for at least a 30 minute boil and the odds of this happening greatly reduce. This is still my process 20 years after my first plugged dip tube.While trying to reduce the amount of trub into the fermenter, i used a stainless steel scrub pad around my kettle inlet as a strainer. After about a gallon it clogged and i couldnt free it with tongs, paddle, etc. So i just reached in with my unsanitized hairy arm and pulled it out. In the end, i still had a mighty fine tasting DIPA and no detectable infection.
Also, clearing a clog by blowing into the drain hose can be just as effective...