It's interesting getting the different perspectives of the 3 responses so far:
1) useful tool for newbies, but it doesn't cover the knowingly overloaded scenario
2) it gives false hope to the user and doesn't take towing capacity into account
3) I'm using too conservative of numbers for a pin weight estimation for fifth wheels
For #1- I don't know how to objectively approach the "towing over your ratings" perspective. I've thought of another calculator that focuses more solely on RAWR and tire load capacity.
For #2- I think it definitely makes sense to add a caveat for the user to refer to their owner's manual or towing guide for further limitations. Though, I'd love to know which took you used , the numbers that you entered ( and for which camper type ) and what your truck's actual towing rating is to try and better the tools themselves.
For #3- I've been round and round in my head with what an appropriate range is for fifth wheel pin weights . My camper has a dry pin at 16% and wet/heavily loaded at 18%. The challenge is that this is for newbies who truly have no idea. My prior alternate calculator was designed to help estimate the actual pin percentage and weight. I plan on adding that, but I still don't know what to do with this utility. I think including as low as 15% is potentially giving false hope when it's a seemingly rarity.