The chronograph is a useful tool for much more that just measuring velocity.
SD and ES are the most obvious results that can be measured.
What about increase in velocity per increase in powder?
I start with a low end amount of powder and go up 1 grain at a time, in an '06 size case, to well above max load in the book. I then shoot each load from the least powder to the max charge. I record each velocity and plot the "hit". As each subsequent shot it made the velocity increases a pretty much constant amount. By the way I never get to shoot the max loaded cartridges. I end up pulling them.)
If velocity isn't where I desire, I go to a different powder.
Also, the chrono will be quite revealing regarding primers. For example when I switched from 30 years of using CCI-250s in a 270 Win to using CCI-200s it was as though I spend a thousand bucks on an accurizing job including new barrel.
At some point, well below the max load cartridge the velocity increase will start to drop off. This is the point where pressure in increasing but velocity is not increasing proportionally. Pretty much the law of diminishing returns. Things are getting inefficient.
Ladder/OCW methods. The chrono is vital when doing either of these or a combination.
Velocity with temperature change. The idea of LRH is to have the first cold bore shot go where you desire. Shoot one shot per day, at the same target, over the chrono, noting the temperature difference and plotting the hit. This will be very revealing. Your measurements will will tell you several things. If your velocity and vertical impact change proportionally with temperture and the temperture swing is small you may wish to finde another "note" as in OCW. Or you could adjust a click or so for temperature. (not recommended - a memory thing).
The chrono used in conjuction with a ballistics program will show you your vertical dispersion at distance without having to shoot that distance.
An example of good luck was when I stumbled on to a load using US 869 in a 338 RUM with 300 SMKs at a velocity of 2735 FPS MV with a consistent ES of +.5 over many shots I stopped dinking around with loading and only pull the trigger when there is hair in the reticle. Additionally as temperature changes, velocity changes as much as 15 FPS but ES remains the same. Out of five shots one of the shots will read 1 fps high. Never low.
Not as good as a book and a bit of a rample but