the ability to manipulate the waveform on the db scale is controlling the dynamics. there are many steps in volume envelopes in Sonar. its not a 1 click on the fly process. the waveform in Sonar is permanent on the db scale even after automation and volume envelopes, which is inaccurate visually.
50/50
First 50 - Ctrl+Drag on the upper portion of a clip will give you a clip gain envelope on your cursor, so it is a one click/step process. If you want to modify after the fact it's Shift+Click. Still one click.
Second 50 - No, the waveform display does not visually change to reflect the clip gain envelope you just modified.
After reading all the posts in this thread I would like this feature too. I think it sounds like a good idea. I don't consider it essential though; i.e., I can edit and mix just fine without it. It's more of a convenience thing IMO. Then again, who am I to turn down a convenience feature.