How can I apply a filter to a function?

I thought I’d go for a two pronged attack in my forum posts, one general (this one) and one specific (the PDeck thread). I seem to have failed on both counts!

I have a function (from the Pdeck plugin) which checks the ‘topic’ field in tiddlers tagged ‘question’, counts the instances of tiddlers named in the ‘topic’ field and plonks a button in all tiddlers tagged ‘topic’ with matching tiddlers title.

I’d like to cut out the topic tagging and just plonk the button in all tiddlers which are named in the Question/ Topic field.