"Questionable usefulness" means that something may not be very helpful or effective, and there are doubts about how useful it truly is. Full definition
That said, all average verdict data is of questionable usefulness in a given case and ankle injury data is probably even less useful than most other types of car accident injuries. (marylandaccidentlawyerblog.com)
While the SCC is clearly not zero, the complexity and assumptions underneath the current calculation process make the FSCC of questionable usefulness in the practical policy debate. (niskanencenter.org)
It was a bold move from Samsung to give a permanent fixture such a specific function last year, especially a functionality with questionable usefulness. (pocket-lint.com)