Paul P
 Can you play notes on your PC keyboard while twiddling knobs on a softsynth with the mouse ?
 

 
Hey, Paul. When I hold a chord on my touch screen, I have to let up on the keys to twiddle the nobs. So, this means I can't hold a chord with one hand and adjust Rapture with the other (all touch). However, I can press the hold button, play a chord, then release the chord and twiddle the nobs in Rapture.
 
Using the mouse does work while holding the chord using touch. So, I can hold a chord with my left hand using the touch screen, grab the mouse with my right hand and adjust values in Rapture.
 
You can also hold a chord with the keyboard and twiddle the nobs with the mouse. I have tried playing it with the computer keyboard vs. the screen. With the touch screen I was immediately able to play melodies. With the keyboard it took some practice and I didn't enjoy it nearly as much. While the keyboard input method is a 'nice to have', I don't think I will use it much.
 
hth

 
Thanks gswitz, this is what I wanted to hear.  Third-party onscreen keyboards, like Chirp that I use, are normal windows applications so you lose focus the minute you click on something else, like Sonar or a softsynth.  This causes problems like stuck notes.  Glad to hear it works in Sonar (I don't have touch).  My real midi keyboard is usually put away to free up my desk, so an onscreen one is useful when just wanting to quickly try something out, like a new sound pack, or in answer to a forum query.
 

I have a 76 key keyboard out all the time that I fiddle with. I'm much more comfortable on the guitar, but the keyboard is a challenge and a bit different from the guitar in the way you approach it.
 
One thing I kinda enjoy about the on-screen controller is that you can slide your finger across both black and white keys to create a fast chromatic run which is pretty easy on guitar, but a bit tougher on a real keyboard/piano. A run in the key is easy (just white keys) but to do chromatic is not the same.
 
I'm not sure it will ever matter, but it was an interesting thing to notice.
 
Also, I find it fun to try to play on the screen tunes I'm learning on piano. At times, I'm constrained by the width of my monitor, but using 1 hand, I can do just about anything I can play on a real keyboard. Perhaps not with the same level of expression, but it works pretty darn well.

I very much like it for VSTi patch auditioning using the QWERTY keyboard, as mentioned previously.   Very cool.  And more ergonomic since my keyboard controller is off to the right of the computer.
 
As to the OP, I would certainly not want to do this and have every single note be a chord!