One of those was a successful recruitment business owner who still recruited hands on.
As surprising as it is, LinkedIn do not stem terms and if you don't do it yourself, you could be missing out on well over half of available candidates.
Here's the example search I did with the business owner...
His search results
Optimised search results
Almost 4x as many candidates found, simply by including stemmed terms.
There are plenty of other variations you could include through the search, but even this simplified example demonstrates how important it is to use all stemmed terms on LinkedIn, particularly for those searches where candidates are already hard to find.
No doubt LinkedIn will catch up on this eventually, but for now, if you're not stemming on LinkedIn then you're at a serious disadvantage to those who are.