1. Why Open.xxx?
   To avoid further complications with short selling the bitassets into existence. To avoid the short selling process for the creation of the bit.xxx assets to be created using the pool reserves funds and the need to block bts collateral. I don't think that the pool reserves should be used for the bitasset creation.Users should create bitassets according to the real demand for those assets.
   I think it is easier to just sell those bts for the 10% annual interest needs of the main bitassets in external exchanges that have liquidity, polo, btc38 (we can sell 9 mil bts equal to $40-$42k in those exchanges easily within a day if need be) and then convert easily those btc, cny, usd to Open.xxx assets. I say Open.xxx assets since Open.ledger supports the bts wallet. Then reward the interest in Open.xxx asset to the bit.xxx asset holders. The users can then change if they don't like the Open.xxx asset to anything they want (bit.xxx, polo.btc, fiat whatever)

2. How would you calculate interest?
   bit.xxx daily balance X 10% X 1/ 360. That is the calculation of the daily interest which to avoid too many transactions can be posted on a monthly basis or whenever there is a transaction.

3. How would you pay interest? Somebody would be doing it manually?
   I am sure that someone from all these smart people in bitshares community,someone can write a simple code to do this process automatically..:)

In reality I would go as far and say that we should sell c$80k worth of bts from the pool reserve that is 20% annual interest based on the current bit.xxx assets supply. If the bitassets market cap goes to $800k we reduce the interest to 10% if they go to $1.6 mil market cap we reduce the interest to 5% and so on...
If we manage by advertising this to increase the DEX trading, people's involvement with the DEX, advertise the huge interest that bitassets holders receive, maintain the pegs which historically have been quite good and we increase the bitasset supply to a couple of millions then bts market cap will be x10 of what we see now. Hence next we can use much lesser bts from the pool to buy the Open.xxx assets to reward with huge interests the bit asset holders..

I feel that either I just had an epiphany today or I am saying something really wrong here so someone should correct me...But I think that something like this has never been implemented because all these years we discuss the interest to be in a form of a bit asset instead of in a form of an external IOU.asset such as Open.xxx and with this way everyone benefits...