In pursuit of Insight, I’ve tried an awful lot of ways of trawling through desk research.
I’ve enjoyed access to experienced desk researchers who come back with 100 pages on everything-you-ever-wanted-to-know-about-air-fresheners and work experience students who think Lexis Nexis is a kind of car. I’ve also done my fair share of my own desk research and produced reports for other people too.
On balance, the most interesting Insights that I’ve ever identified (without the benefit of primary research) have been when I’ve done the digging myself. 
Although it is immensely time consuming, no report, however well written or thoroughly researched, can replace the dawning realisation that three or four of the things you read this morning have something interesting in common that you hadn’t considered before.
In the frantic world of agency life it’s very tempting to offload desk research onto a specialist or the nearest junior, but I’m definitely going to make a conscious effort to do more of my own groundwork.
If you want to grow great insights, maybe you have to do the digging yourself.