Clarify 10% agreement with simulations

[wadawson]

This is a request of the referee:

In the abstract (and elsewhere), results from this method are said to be in agreement with N-body simulations to within 10%. While the phrasing given is technically accurate, given the context it is easily misinterpreted as meaning that, given a set of observables, the inferred parameters of the merger agree with those from numerical simulations matched to a particular observation at any time t during the merger (at least that was what I came away with from my initial reading of the abstract). The test that was actually done was to take known parameters from the merger (including d_3D(t_obs), which is not an observable), run this single case through the model (with no Monte Carlo analysis to consider errors), and show that the output v_3D(t_col) and TSC_o are within 10% of the values found in the simulation for the given merger state only (i.e., at t_obs). Although the way this is currently described in the paper is fair, the point could be clarified with some minor changes in language.

[wadawson]

Response to the referee:

I adjusted the abstract (and elsewhere) wording with regards to the stated accuracy of the method. The wording did not need to be changed dramatically, especially since the main issue noted by the referee was largely addressed by the improved Springel & Farrar (2007) comparison work of Section 2.3.