This could point at an earlier step in the pipeline - e.g. the recruiters at those companies may have been using LinkedIn as a primary search tool - but that's a signal of its own.
However, you can double your income by thinking differently about LI. If that doesn't speak to its value as a network, I might need to reassess what network value means.
How? I would love to double my income.
2. less LI, but become a thought leader
3. Network, write, promote. People are more likely do business with people they "know" so make sure they see your face on a regular basis.
4. Sales skills and business acumen, you will need this if you want to break out of the average