The scroll of tack improvement has been modified, again.
It used to add 5 points to the shape of tack.
Now it adds 5% of the total.
What this means is that the scroll will almost stop the natural degradation of tack (the nightly 5%)
Shape = Shape * 0.95 * 1.05 = Shape * 0.9975
The scroll only works for tack with shape lower than 1000.