Circumstances are secondary. The mechanism will be used when people vote for it to be used.
That said, I like the idea of not inflating the NBT supply as a fix the for an oversupply of NBT. I look at it like this. There has to be an incentive for people to absorb an oversupply of floating NBT (parked ones are not the issue, as long as they are parked). The incentive has to match the risk associated to locking in the NBT. Offering NBTs on parked NBTs is buying time and "kicking the can down the road".
If people who were parking NBT's were offered shares in return instead of NBTs, there would be shareholder dilution. I can see how shareholders would like to put the risk should on the holders of NBT's, offering an interest paid by future users. If share holders would instead be paying be diluting their own holdings, I think its likely that would be more reluctant to do this, since they would be paying for the peg out of their own pocket. However, if only new NBT's are issued when demand of NBT's outstrips the existing supply, the system would always be 100% solvent as long as the proceeds are not squandered. Hence new share paid out as an interest on parked NBTs would only have to be issued, if the system has somehow wasted these profits.
Just to be clear. The proceeds generated by the system have to somehow be retained in the system, otherwise the peg will not be 100% backed. I think the system could get away with less backing then 100%, so some dividends could be paid out, some new shares could be issued as parked NBT.
Basically, if shareholders are to greedy, taking out to much dividends, they will strip the system of its wealth. Issuing new shares, diluting the existing, is the punishment for being greedy and not saving for a rainy day.
A twist on the whole thing could be that new shares are never issued either. Instead the cost is socialized and all existing share holders have to give up a fraction of their holdings, to the parked coins. That way there is no share holder dilution. Since the number of shares stays the same, the price of a share should not be affected.
I've not thought it through though. I'm confident there is an issue with my proposal as well. I'm also pretty confident that no-one want's this kind of system either. I think shareholders wants a continuous stream of dividends, siphoning out the money coming into the system. Then they say to themselves that if things seems to go out of hand, they will simply sell their share and hope to be among the first ones heading for the exit.
The system will take in money. If this money is not retained within the system but stream out, the solidity of the system will erode. That's a fact. People and developers want there to be a stream of money. The whole question is whether or not shareholders will be able to hold back on their greed and only leach as much out of the system, relative to how much it grows.