16 minutes ago, Simon Retold said:A strict reading of the rules says that no, it could not be doubled up for a single attack. Let's look at the wording:
Here's the Control upgrade: "Once per round, when an attack targets the Force user, he upgrades the difficulty of the pool once."
According to this, the upgrade is triggered by the attack.
Here's the Duration upgrade: "Sense's ongoing effects may be triggered one additional time per round."
This makes it plain. If the attack is triggering the Control upgrade listed above, it would take a second attack to trigger it one additional time .
Just as an aside on a beaten horse - even if you could stack the triggers, at best you'd get three upgrades on a single roll, not four. The power is triggered, strength upgrades it once, duration retriggers strength, which upgrades it once.
I 100% agree that it can only be triggered once per attack, though.
Edited by Dunefarble