I didn't address that because I don't think people are very interested, but you don't seem to know what you're talking about.

The field that holds the seeds is created on the fly when you click 'randomize'.  I can't change the value in a field that doesn't exist.  If the "randomize" dialog isn't visible, the seed field doesn't exist.

  socket.on("shash", function(data) {
    $("#shash").html(data)
  });
  socket.on("seed", function(data) {
    $("#seed").html(data)
  });
...
  socket.on("nonce", function(data) {
    $("#nonce").html(data)
  });

So what? Unless dooglus has psychic powers, he can't tell how you're going to bet.  Are you betting high? Low? 49.5%? 20%? 10%? Martingale? Progressive strategy? Bet 0.1 but 1.0 every tenth bet?  He doesn't know.  Therefore he can't create a seed that will give you unlucky numbers for your particular betting strategy.

No, by default the game is provably fair.  Provable is an adjective, it means that something is capable of being proven.  Just-dice can be proven to be fair.  As Doog explained, the user just has to take certain steps to do that.  And, as far as I know, of those who did take those steps, just-dice has been proven fair 100% of the time.  

Every user has the ability to prove that the game that they just played is fair.  It sounds like you just want the site to make it easier for users to prove that the game is fair.  Doog's position appears to be that the benefits of that, if any, are outweighed by the negative impact those changes would have on user experience.  If anyone disagrees, I'm sure there are other dice sites that make it easier to prove fairness, and if not, create one!  Maybe you're right, Doog is wrong, and users do prefer the steps to prove fairness to be easier, even if it requires changes that may be a detriment to the user experience.  Maybe there's some room for innovation there, and it can be done with little to no cost to the user experience.  

The point is, the game is fair, and with some effort that can be proven by anyone playing it if they follow Doog's instructions.  Just-dice is provably fair to gamblers.

The potential for anyone in Doog's position to do something dishonest (walk away with investor money, cheat his own site, switch the game with a different game that is unfair) has nothing to do with the fairness of the game.  That potential exists whenever someone must place their trust in someone else.  You can never prove that there is a 100% chance of honesty.  But you can make a rational, informed judgment, and all things considered this seems to be a pretty safe one considering the various incentives, at least in this context (I know little about and can't comment on whether the site is safe from hackers, for example, though it is a pretty big target and as far as I know other than a manual payout mistake early on, not much of any has been lost).

Your thread subject, "Just-Dice is not provably fair to gamblers" isn't accurate.  More accurate would be "Just-Dice is provably fair to any gambler who cares about provable fairness and can be bothered to take the steps to verify the proof".

This game is provably fair*

*At Just-Dice, those steps are:
1) make a note of the server seed hash
2) set your own (unpredicable) client seed
3) play as much as you like, making a note of your rolls
4) verify the rolled numbers

Generate client seed client-sidedly.