RussNot sure if I understand what it is you are seeking. I installed a trolling valve in my boat over ten years ago, and it truly did help. My particular valve reduced my idle speed from 3.5 knots to 2.3 knots approximately. Much better for trolling King Salmon. As to concerns, the only ones I would have are whether you should be running your main engine at low RPM for extended periods. With my limited understanding, nearly any diesel that can maintain close to optimum cylinder temps while fishing is not going to be harmed by doing so. My trolling valve cannot be run over 1,000 rpm, which doesn't keep my temperature as high as I'd like, and at that rpm doesn't go slow enough for ideal King Salmon speeds. Only by running at dead idle am I able to go slow enough. This slow running can be compensated by getting up to a good hot cruise after fishing, thereby cleaning up the cylinders. However, as Fred says, your bottom line decision should be determined by a quality Cummins mechanic, with full understanding of the transmission/engine combination, and the actual trolling valve you will use. Once you determine what rpm you'll run at, then he can tell you what problems you might suffer.
I haven't really used mine as much as anticipated, due to my wife's inability to deal with slow rolling motion. She barfs all over my fresh caught fish. So, I really can't speak beyond what I have said.
Good luck, Carey