How does Find Traps work?

I opened the manual with a better OSX PDF viewer than Preview and managed to find the Thieving Abilities section where this skill is documented in some detail. From the book:

Thieves can select Find Traps, and they will look around for traps until otherwise directed. At the start of each round while the Detection mode is active, the Thief’s Find Traps skill (modified by a simple d10 roll) is compared against any traps within sight of the Thief. If the Thief’s modified skill is higher than the difficulty rating of the trap, the trap is detected. Note that this skill does not benefit from having more than 100 points assigned to it.

So it should only be necessary, most of the time, to wait 6 seconds for the start of the next round to detect any traps within sight. I ran through the level again and this seemed to hold true. Earlier, I might not have consistently remembered to reactivate Find Traps after reactivating Stealth. I'm still curious about how the Find Traps skill is modified, but it sounds like the d10 is added to it, since otherwise it would be useful to have up to 110 points assigned to Find Traps. Assuming that traps can have a difficulty rating up to 100.