And even uto update will not update till you release the node!
Yes japunto is right let me clarify a bit: the reason it needs a keyframe is that if theres no keyframe set it has nothing to update form se maya is lazy evaluator wich is why ist so fast, but thsi also means changes arent comitted untill they realy are.
Se the curve reads the animation values but untill you set a key no animation value has changed the animation is still the same (another side effect of thsi si that if you now release the move and change time maya forgets your move).
This is a solvable issue but doing so is in partial contradiction to how maya works internaly and would make the node less uefull from mayas every node has to work witha ll other ndoes in the framework idea. Offcourse the way maya is rigged now you can visualize even more as it can as easily viualize even expressions. but it is possible by inserting a new temporary node in the network instead of the anim curbve and once comitted swap it back. Now thsis would be something i wouldnt want to be implementing.
[Potentialy it would be possible to just mark the change dirty!?! oh sorry thhe trnsform must prject clean otherwise keyframing would become impossible but yeah temprarily swapping the anim curves would work, even on other nodes on top buts not a elegant solution]