Yes it is. You can't cover much shoreline without one. Also, there is limited shore access on Clear Lake due to all the private lakeside homes plus so many motels and campgrounds. As far as where to fish, unless you're in a fast bass boat, what part of the lake you're staying at is a factor. It's a big lake with many, many good spots.
I should have asked you what part of the lake you would be staying at so please give us that information. I'm not going to suggest many spots because I haven't been going out but there are several members on here that can help you.
I will give you some spots that almost always produce fish: Try Shag Rock mid-lake, the south end starting at Rattlesnake Island, Clearlake Oaks Canals, Wheeler and Leubow Points and the Monitor Point area. In the north end try all of the Nice and Lucerne shoreline, Rocky Point on the Lakeport side. Actually, just about any pier and or floating dock produces fish but of course, some are much better than others. You can get a lot of information from any of the Bait & Tackle shops listed on my
fishing report page.