23mm is a lots slower, I’d wager a good 40mm actually be better than the horrifically small 23mm that a lots of tyres manufacturers nowadays no longer make.
IMO 'real world' comparisons for me would also include me coasting, lifting my bum, and holding my breath on every other pothole on 23, vs gently shifting weight and still pedalling on 42.
23mm is a lots slower, I’d wager a good 40mm actually be better than the horrifically small 23mm that a lots of tyres manufacturers nowadays no longer make.