I don't prick my eggs, but then I never put cold eggs into boiling water either. If you do prick them it's the round end that should be pricked, that's where the air pocket is. Don't put the eggs in too large a pan, that can as cause cracking.
Just to give you all a giggle, here's my recipe for boiled eggs for soldiers. Put the eggs into pan of cold water, bring them to the boil, then reduce the heat and sing three verses (and choruses) of Onward Christian Soldiers and et voila!!!! Perfect boiled eggs!