Sometimes you'll hear people refer to Liver Training School (LTS) - eventually (well, hopefully) the kitty's body will adjust to being in the lower numbers and then stop bouncing once the liver feels "safe" with those greens or blues or yellows. Sometimes they don't have to drop very low - the liver will sometimes kick in if they drop too fast. Some people give frequent small meals, especially early in the cycle around onset time, to steer the curve when they know their kitties are prone to quick drops.
One one hand - it's good to know that the liver is keeping your kitty from dropping too low - especially if you are out most of the day. So, in that respect, coming home to a high preshot number isn't all bad if you suspect that they dropped low or fast during the cycle. On the other hand, it can be incredibly frustrating if you have a bouncy kitty that just doesn't seem to settle into that wonderful. sort of flat lantus curve.
I used to think of it like a pendulum - high on the ends at first and eventually settling down to a much flatter curve...