This seems odd to me. As an example I made a workflow that runs an NSAppleScript like so:
on alfred_script(q)
delay 10
display dialog "hello world"
end alfred_script
The dialog appears immediately without the delay. When I run this script in the AppleScript editor it works fine.
Of course I'm not intending to make a workflow that makes a 'hello world' dialog, but what I am trying to do requires delay to work.