Al,
You can cheat by running the bar a little above center. This has no ill effect unless you are taper boring.
Sometimes, you have to modify the tool a wee bit to make it fit, such as mill a little bit off the back side of the bar, opposite the insert tip. Or, go to the next size smaller bar, but this can often cause more vibration trouble if working at the limits of overhang to do a given bore.
First you get good, then you get fast. Then grouchiness sets in.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)