I will look into this a bit tomorrow. Can you supply an example command-line invocation?
This blog talks about the tool for automated testing. It's kinda "complicated" to setup. In the blog, he eventually gets to a commandline:
instruments -t /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/Library/Instruments/PlugIns/AutomationInstrument.bundle/Contents/Resources/Automation.tracetemplate "/Users/jc/Library/Application Support/iPhone Simulator/5.1/Applications/C28DDC1B-810E-43BD-A0E7-C16A680D8E15/TestAutomation.app" -e UIASCRIPT /Users/jc/Documents/Dev/TestAutomation/TestAutomation/TestUI/Test-2.js
But there's a lot of setup, so =/