When not to use an adhesive caulk
Adhesive caulks certainly have their place, but they are probably the most misused caulks out there. Most people who use them indiscriminately, end up regretting it. Adhesive caulks, such as straight polyurethanes, should be used only in applications where you will never want to remove the item, such as a deck to hull joint. Other than that, nearly everything on the boat is subject to removal for repair at one time or another, either due to accident or wear. I had a gentlemen relay his experience where he used an adhesive caulking on a transom plate of his boat figuring he would never want to remove it. After a couple of years, he decided to repower the boat. In his efforts to remove the transom plate (by actually lifting the boat by the transom plate) the entire transom came off. Keep in mind when deciding to use an adhesive caulk that whatever surface you are affixing something too will most likely be damaged by trying to remove the object at a later time. Also you do not want to use an adhesive caulk in any area that is exposed to sunlight as it degrades with UV.
