You will get more bites, therefore catch more fish of which many will be smaller, on smaller baits. But there will be large fish caught on small baits as well. I have fished ultra light tackle from Lake Fork and Bob Sandlin, where I normally fish, to Fort Phantom in west Texas, Table Rock in Missouri, and every lake I've fished in between. Light tackle works everywhere. It can work when nothing else will, which is what I like best about the technique.
Light tackle is so versatile it can be used on any lake at almost any time of the year.
For a serious tournament angler, this versatility can make the difference between getting a check and going home with the blues. In my experience with ultra light there are two components that can be put to good use in bass fishing. I like a Zebco spincast reel when the bass are biting super light. You can cup your hand over the reel and run the line across your index finger for maximum sensitivity. The reel is great for accuracy and skipping a gitzit or grub under boat docks.