don't be silly, Nick
The vertical scale could have been from 0 to 1,000,000 ppm and the graph would display only a straight horizontal line. would that have been better?
The fact is the data shows a rapid 20% increase in CO2 levels that is temporally correlated with anthropogenic CO2 production- that is the important fact.
I worked on an experiment looking at the energies of electrons ejected in laser induced ionization. Much of what was important about the data would not show up on a linear-linear plot. However when plotted on a log/linear graph it was clear that some electrons had energies in excess of what some theories predicted. So was presenting my data on a log/linear plot dishonest, or just common sense?
You are a scientist Nick... You should know better.