Effort is simply one tool in your DM toolbox. When it’s the right tool, it does its job beautifully. When it’s the wrong tool, then it might bog down your game.
When is effort the right tool? Effort is the right tool when you want to slow down your game and elongate time. Why would you want to elongate time? You might put a task on the PCs they have to complete. While they are busy taking time completing the task, pressure is mounting. If your goal is not to build pressure, then adding Effort to your game is not the right tool.
What are some examples? It might take PCs one heart of effort to chop down a door; pick a lock; call an elevator; create a device; hack a sentry turret; stop a ritual; close a portal; or persuade a reluctant witness. When is the right time to force players to spend their time engaging in such tasks? Whenever pressure is mounting. The dragon is coming back. The guards are running up the stairs. The roof is about to collapse. The fire is spreading. The enemies are showing up in waves. The bad guys are harming innocents.
If you add a timer to the mounting pressure, e.g., the lava is rising in 1D4 rounds, and then you force the players to pick the lock to the door and apply effort to slow them down while the lava is rising, I guarantee that players will feel the literal heat trying to avoid burning alive. Using these tools, a Timer in conjunction with Effort, can add much needed excitement to your games.
If players have all the time in the world, or you are not trying to slow them down, then Effort is not the right tool for the job. Hope this topic helps folks on this important concept in ICRPG.