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\section{Introduction}   When a quasar is lensed into multiple images by a foreground galaxy, the observables of the lens images are their positions, magnifications, and the time delays. These observables can be used to directly measure both the structure of the lens galaxy itself (on scales $\geq M_{\odot}$) as well as cosmological parameters. In particular, while it has recently been proposed to use time delays to study massive substructures within lens galaxies [REF], \citep{K+M2009} (Keeton \& Moustakas 2009),  they have \emph{already} proven to be a powerful tool for measuring $H_0$ [REFS]. The accuracy of $H_0$ derived from the data for a given lens system is dependent on both the mass model for that system as well as the precision measurement of the lensing observables. Typically, positions and fluxes (and occasionally shapes if the source is resolved) of the images can be obtained to sub-percent accuracy [REFS], however time delay accuracies are usually on the order of days which represents a few percent accuracy for typical systems. This is compounded with the fact that measuring time delays requires continuous monitoring over weeks to years, and, as one might expect intuitively, the measured time delay precision does not significantly exceed the sampling rate (or time between epochs).