The prevailing wisdom from the east side of the Atlantic seems to be that it was a bad idea. It's done from time to time on the western edge. Seems like there were 3 options:
1. Ride the brakes during taxi
2. Pull over somewhere with the power above idle
3. Pull over somewhere with the power at idle
1 & 2 will result in higher brake temps. The OP said 2 units. What's the maximum for takeoff? If it's 10, I hope it shouldn't be a problem.
Options 3 would keep the brakes cool, but may not have been feasible due to some time constraint.