Well, I personally think that most behaviors performed by most species are pretty fascinating, and its even more interesting to see it first hand. I have found with most Tylototriton in the genus that they are are generally quite lively and "bold" with the more human interaction they have, however in a zoo environment they will not be able to expect as much human handling/hand feeding etc etc as they would from a Private keeper/collection. At the end of the day there is going to be tons of work for a Herptile Department in a Zoo, so their human interactions they would require to keep them as such would be quite difficult to achieve.
Don't forget, most of these species in the genus are in fact more Nocturnal or Crepuscular (excluding a few species such as the Guizhou Crocodile Newts (T.kweichowensis, striped and spotted), Himalayan Crocodile Newts (T.verrucosus) and maybe the Emperor Newt (T.shanjing) which are kind of all varied in captivity). So it is kind of a big reason as to why Zoological Collections don't really have major displays for some of the species such as the Wen Xian Knobby Newt (T.wenxianensis).
T.wenxianensis: I have found with my Wen Xian Knobby Newts, that they are largely Nocturnal, coming out to hunt purely at night periods. However, this behavior does appear to change drastically from Keeper to Keeper. I have found that they will pretty much perform the natural behaviors such as Mimicry (Playing dead) regardless of being CB or WC and as soon as they know your hanging about watching them they will simply freeze, and then as soon as you turn your back and look back again they would of gone to a hiding spot. However, like with most animals with a little bit of human contact they would become more bolder.
T.kweichowensis: I have found that the Guizhou Newt (T.cf.kweichowensis) is actually quite bold and seems to be active pretty much constantly and certainly not afraid to get some food if you offer it. The Guizhou Newt (T.kweichowensis) seems to vary with its behavior, which of course varies from Keeper to Keeper.
T.taliangensis: For the Ta Liang I have heard and found its practically the same as what Foster said, its really does vary (like everything else I have said) from each Keeper.
T.verrucosus: They are pretty much what Julia and Mr Cyclone say, they are bold as brass and seem to be not bothered by people. However (yes I am saying it again lol) this seriously varies but generally they are lively buggers.
T.shanjing: Same as the Guizhou personally.
For the members of the public, some of these behaviors for some of the species such as Wen Xian would have to be provoked which causes unneeded stress, especially if you would constantly have to dig them out of their hides to show the public whats in a apparently "empty" enclosure/display. To actually see a zoo with an exhibit and conservation programme for any Tylototriton species would be amazing, it's about time that they had some publicity as a lot of non-amphibian people don't have a clue what one is which is a shame in my opinion.... Rant over