Scrubbing with linked numbers gives wrong values during scrubbing

[dbieber]

As an example:
Type "10 + 10 = 20"
Link the two 10s together.
Now scrub so that the 10s become 20s and it will read incorrectly
"20 + 20 = 30" until you let go, at which point it will say correctly "20 + 20 = 40".
It's using the old value of the linked numbers for all instances except the one you're actively scrubbing on.