I have been breeding Jacky dragons since the early 1990's and keeping them much longer. The animals I have now in my collection are descended from some of the original breeding efforts from that time. Even after all this time of captive breeding and generations of animals in captivity, my individuals still demonstrate skittishness and instinctive reactions to take flight as soon as I try to handle them. They are reasonably comfortable with me and others in the room with them and in fact will actually more often then not move forward to the front of their enclosures because they associate my presence with food.
They will tolerate cleaning and changing water bowls etc, because they are used to it, but any attempt to handle them will always result in them trying to avoid the contact. This is because I minimise the handling of my animals to only when absolutely necessary and as a result my Jacky's have not been "conditioned" to handling and so instinct kicks in and they retreat to avoid it. This is despite being captive bred for over a dozen or more generations.
In all my time keeping Jacky's I have never offered them any form of vegetable matter for food. I always provide a variety of well fed (with vegetable matter) insects that are dusted with a calcium supplement and multivitamin powder. It is my experience that most dragon species are actually stimulated to feed by the movement of the insect. Many times I have dropped dead crickets, woodies, locusts or other feed insects into an enclosure and observed that other then noticing the insect actually hitting the floor of the enclosure the dragon will quickly loose interest if the insect does not make any further movements.
Contrast this behaviour by conducting the same "experiment" with active live food and it is easy and appropriate in my opinion to conclude that live insects as food is more then likely going to get the dragon feeding and therefor give you the best results and success when maintaining your animals. Even jerky, twitching movements on the spot will usually get the dragons interest. I have also noticed that most dragons try to pick up food items by the head first and will usually wait until an upended insect rights itself and starts to move forward before grabbing it to consume.
I have no doubt that some animals can be "conditioned" to take food other then live insects, such as vegetable matter and even recently dead insects, but it becomes a matter of how far do you want to push the conditioning process.
In my case with a reasonably large collection to manage, animals feeding easily and readily allows me to concentrate on animals that become fussy and difficult feeders. Crested dragons have a tendency to become difficult feeders as indeed do earless dragons. Very often I have to resort to individual feeding and monitoring of one animal in order to make sure it maintains condition. This may involve picking out freshly molted insects or disabling the insect to make the food easier for the dragon to catch.
Having my colonies of Jackies feeding readily on gut loaded well fed and dusted live insects ensures I can put the effort into other animals and species that require more attention. I minimise handling because it is stressful for the animal involved, which can also lead to and cause feeding disorders and or refusal to feed. Even though over time the animal will get used to it, most species including the various Bearded dragon species are initially very stressed by handling. Only a very few get used to it (beardies, angle headed's, boyd's and to a lesser extent frillies) quite quickly and even over time with repeated handling become conditioned to it and allow handlers to pick them up without too much if any negative response at all. I have never seen this with Jackies in the 35 odd years I have been keeping them. They will always resist the initial contact, then for those that are conditioned will settle so that they will sometimes just sit in the palm of your hand, but as stated previously beware because first opportunity they get they will try to escape as indeed will most dragon species, captive bred or not.
I guess if you want to handle your animal then your best bet is one of the bearded dragons species . They appear to accept handling readily
Hope this helps