Indeed, that is how Bull Endurance works, and how I would currently interpret the Stranglevine. It all depends on how we decide to handle the changing variable though with regards to time stamps.
Here is my original post discussing the possibilities.Option 1 basically erases the past, allowing Finite Life to cancel all of the Life gained, past and future.
Option 2 is like a historical revisionist, rewriting the past and increasing a trait that already exists without the game registering any changes happening.
Option 3 seems the most likely to me. By having a separate time stamp for each change in the variable, we're able to keep past gains while preventing future ones, which is how Finite Life tends to function.
Also, to apologize for the confusion, although sIKE was advocating a similar effect in the end as Option 2, he was advocating a completely different mechanical route to get there by suggesting we errata the card to use the Innate Life trait instead. Which, I can definitely see merit in his suggestion, but barring errata the only interpretations I can come up with for the current card are the three mentioned and only the last one actually makes sense to me. If the others make sense to you though, I can't say with any authority that your wrong, only that the other two options seem silly to me personally.