I always found his chart to have too low front pressures also, but again, see how x and y and z pressures feel to you, over bumpy stuff and around corners.

My suggestion is to start higher and then take 5psi out at a time, you'll quickly get a feel for things.

Am I the only one who finds bar numbers overly , not sure the expression, but 4 bar is 58 psi and 3 is 43-44. Big big difference.
I guess you just have to get used to .1 or. 2 bar differences, and I'm clearly used to reading psi marked pumps and gauges.
Seems it is easier to make large pressure errors for someone not paying attention to the decimals.

Anyway, like all things in life, it's the details that makes the differences.