Hi,
yes, you could create a new calculated member in “Summary” dimension to aggregate a filtered set of dimension members using regular expressions.
But such a method would be slow to calculate if you have many members in the “Summary” dimension.
A bit faster way would be creating a new calculated field (and import as a separate dimension ) with Javascript in advanced settings that splits all issues in two buckets (those where summary starts with a prefix and others) then filter the report by selecting a filter in new dimension.
Martins / eazyBI support