That is the “coind day” equivalent. This encourages people to set aside fund. Another way is reward based on fund. This encourages people to get fund from somewhere else quickly. The first method may attract less fund in an absolute sense.
Then people will see that a T1 wall gets low, Nu gets T3 fund for this wall, but the T1 LP doesn’t use the fund (at a price within tolerance). It’s easily identified and punishable.