You people use math when utilizing the airborne radar???
Above FL300 0 degrees tilt is a fine place to start in the CRJ-200. Tilt down until you see ground clutter behind the weather to see the lower moisture/energy, then tilt it up until the return starts to dissipate to see the moisture/energy in its upper half. Find the middle ground that works best and leave it there. If there's a shadow behind a cell, DON'T FLY THERE.
I also used to Gain up +1 in the CRJ to help avoid the worst weather when trying to pick through a line...NEVER gained down though.
I'm certainly no Dave Gwinn or Archie Trammel, but the guy that taught me hands-on to use weather radar has a Ph.D in synoptic meteorology. He didn't bother with any mental gymnastics when flying around thunderstorms...just adjusted the tilt until he saw what he wanted to see.
And for full disclosure, we have a Garmin 496 in our Citation for the sole purpose of datalink NEXRAD. Between it, the factory airborne radar and the good ole' Mk. I eyeball, we've yet to have a problem working around the worst of southern and midwestern thunderstorm lines.