Slim,
As noted in my first post on powder, nothing is free. The tests in Hodgdon's data are shot inside temperature-controlled rooms at 70 degrees. Yes, Hybrid 100V is the "fastest" powder with 90-grain bullets (by exactly one fps over H4831), but H100V is also one of the less temperature-resistant powders I've ever tested. In a trial a few years ago with several powders and 165-grain bullets in the .30-06. H100V lost 176 fps between 70 degrees and zero Fahrenheit.
Since H4831 is one of Hodgdon's Extreme powders that are very cold-resistant, it doesn't normally lose any velocity between 70 and zero, which means that the "advantage" of oh-so-modern H100V would disappear with a drop of about half a degree in temperature. I've found this sort of temp-sensitivity to be common among newer powders designed to produce top velocities at 70 degrees.
The REAL advances in powders haven't been extra velocity as much as other characteristics, such as consistent velocities over a wide range of temperature.
