The picking procedure relies on a well-yielding tension wrench. The tension wrench has to be lightly spring-loaded so that the pins can bypass their false breaking points. You also have to "rake" (seesaw in and out) the pins with your pick. The feather-touch tension wrench is ideal for the job. Use light pressure with it, and it will let you in.
(Note: A feather-touch tension wrench is not necessarily required. A normal tension wrench will work fine with an extremely light tension on it. The weight of just your index finger alone should be enough in most cases.)
The mushroom and spool pins are used in locks for high-security purposes such as bank doors. The American Lock Company uses them in some of their padlocks.