This may be similar to http://splunk-base.splunk.com/answers/2218/adding-intention-to-second-drilldown-search. I have a dashboard with the pattern SearchSelectLister->ConverttoIntention->ConditionalSwitcher->HiddenSearch. I wanted to add a second intention before the switcher, so I stuck an ExtendedFieldSearch just before it. The result was that neither intention was substituted into the HiddenSearch; I was stuck with the $foo$ text. I changed the ExtendedFieldSearch to another SearchSelectLister->ConverttoIntention, to get a dropdown instead of freeform entry, and that worked. Did the ExtendedfieldSearch somehow consume the original intention? In general, how long do intentions stick around--are they only converted when they hit a search module, and does it matter whether they're stringreplace or addterm?
UPDATE: I tried to reproduce this problem on an example dashboard and couldn't. However, on this sample dashboard, the ExtendedFieldSearch only works when it's a child of the search module I'm substituting for. The SearchSelectLister works as the search's parent. Why is this? I find it more intuitive for the intention modules to contain the searches, and I'd prefer to do it that way for all intentions if ExtendedFieldSearch can be used like that.