Yeah, it flat out will not do it better than about what you've said. I'll mess with it on my way into Minneapolis on Saturday to annoy
@ClarkGriswold and his coworkers.
I also like using the performance data to determine what the estimated crossing altitude for each fix is too, if it's on the high side I know there'll be a deceleration problem. Figuring out tricks is fun, for sure.
I will not abide sloppy flying. That may be how they do it at Southwest (ducks!), but it is not how I do it, especially considering the fanatically accurate navigation precision I have.