Saving Functions as variables

So today I was working through code and I saw a function that was being called multiple times however with only one single differing variable. I assume that saving this into a local variable like this is exactly why advanced evaluation exists.

load(
  local!allReviewOutcomeTypes: rule!LE2E_getAllReviewOutcomeTypes(),
  local!grabCaption: displayvalue(
    _,
    local!allReviewOutcomeTypes.outcomeTypeId,
    local!allReviewOutcomeTypes.outcomeType,
    "Error Invalid Outcome Type Id"
  ),
  {
    a!documentImage(
      document: a!iconIndicator(
        "WAIT_CLOCK"
      ),
      altText: local!grabCaption(cons!LE2E_REVIEW_OUTCOME_TYPE_REQUESTED),
      caption: local!grabCaption(cons!LE2E_REVIEW_OUTCOME_TYPE_REQUESTED)
    ),
    .
    .
    .

However I'm curious about another case that I'm wondering if I can use this.

I have a large interface which uses queries to create a psuedo real-time grid. However because this uses the query in so many places I'm concerned about keeping them all up to date. What I'm looking at is adding a useless input with no effect, then I can save the query as a function rather than allowing it to evaluate at the time its saved and then pass that local variable around to guarantee that they are all identical. 

I just have a few problems, first of all, the query doesn't seem to work unless its a with variable whereas the first example (displayvalue) worked in a load, why is this? It is returning null so my first instinct is that its losing track of the parameters I previously passed.
What is Appians stance on this, is this recommended/discouraged?
Are functions meant to be able to be passed as rule inputs and if they are why can't I select a 'Rule or Function Reference' value for my rule inputs? Or was this behavior meant to be reserved for Appian functions like reject or any which expect to be passed a function, or for functions like sum which can accept unlimited parameters?