Im admittedly brand new to the game and am only now learning the system but it seems to me that the ability of the player to improve his chances at almost anything substantially by committing to the Doom pool is so obvious as to almost never be avoided? Yes, I understand the GM can make things more difficult for the players when he has Doom at his disposal but given the chance to not fail or really, really succeed at a test I just dont see the typical player EVER turning it down.
Am I wrong? Does it play out differently in actual play? Im soloing the Vultures of Shem adventure as a learning tool and Im actually have a hard time coming up with things to spend the continually replenishing and usually growing Doom pool.