I know boiling points. All those chemistry and chemical engineering classes and I'm a somewhat serious cook. I agree with Jim W's conclusion.
You wouldn't drink soup salty enough to have a boiling point more than a degree or two higher. A cube of bullion? Not a factor as far as boiling point goes.
If you add a cup of sugar and start making carmel, sure, get to "soft-ball" or "hard-ball" and you can get 30-50F higher. But I don't think any ULers are making candy at 9,000 feet.
The two factors I do see as potentially significant when boiling non-pure water are
1) boil over which wets the pot, wets the flux ring, and transfers heat to the canister. And
2) the ions in something like bullion on something made of dissimilar metals. I haven't looked up the electrochemistry of Ti and Al, but some poorly choosen metal combinations can corrode away in minutes in salty water (nickel and copper, I seem to recall).
I'm packing for a family BP trip now, so I'm not going to do the research myself, but just on the face of it, it seemed odd to me that JB would mix Ti and Al in one pot given that it obviously heat cycles and some people (me, for instance) go sea kayaking and beach camping with our gear and expose it to some salty water. Sticking with one material throughout would havve made for a much more robust design.