The general consensus around gravel tyres is that wider is faster. Professional riders like Dylan Johnson have been banging this drum for a few years now, and nearly every pro bike we saw at The Traka last year had the limits of clearance pushed to the point that paint was definitely going to be removed should things get muddy, which they did.
This has been somewhat fuelled by our own studies last year into road tyre width, where we concluded that wider road tyres were faster for nearly everyone, even going up to 40mm slicks.
