My experience is quite the opposite : if you do not give a deadline, the work takes much more time, people are goofing off (especially me), knowing that anyways, they will have enough time. A deadline forces you to focus right now, not to experiment on new ways of doing things. I often ask for deadlines in my job, it makes me much more efficient. That said, if the deadline is not realistic, it does not hep either to motivate people and furthermore, it is often necessary to try new approaches, just not all the time. As often, it is a question of finding a good balance.

Having used GWT for the whole past year, I can ensure you that using it does not totally feel like writing desktop apps. You definitely still have to understand very well how the DOM and css properties are working to obtain nicely looking and mainly, nicely resizing pages. Furthermore, since, in the browser, you do not have direct storage available, you are relying very much on asynchronous calls to a server to obtain any kind of persistency, which makes theh process very differnet than writing to files. That said, I must point that manipulating complex data structures is really easier using java compiled to javascript than directly using javascript (if only for the debugging facilities offered by GWT). My point is : GWT definitely helps you write slick web app looking like destop app, but the abstraction remains very leaky.