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Multi-site campaigns coordinated across the globe via the Whole Earth Telescope (WET, \citealt{1990ApJ...361..309N}) have proved the richness of well-resolved WD pulsation spectra. For example, less than a week of nearly continuous observations of the helium-atmosphere (DBV) GD\,358 revealed more than 180 significant periodicities in the power spectrum, providing exquisite constraints on the helium-envelope mass, $(2.0\pm1.0) \times 10^{-6}$\,\mstar, the overall mass, $0.61\pm0.03$\,\msun, and the magnetic field strength, $1300\pm300$\,G \citep{1994ApJ...430..839W}. Similarly, roughly 11 days of nearly continuous photometry on the pre-WD PG\,1159$-$035 revealed 125 individual periodicities, accurately constraining the mass, rotation rate and magnetic field of this DOV \citep{1991ApJ...378..326W}.  The hydrogen-atmosphere DAVs have also been extensively studied by some half-dozen 10  WET campaigns, with varying results. results and degrees of success.  In part, this is a result of how pulsation modes excited in DAVs are characteristically influenced by the WD effective temperature: hotter DAVs tend to have fewer modes, lower amplitudes and shorter-period pulsations, while cooler DAVs driven by substantially deeper convection zones tend to have more modes at higher amplitude and longer periods \citep{2006ApJ...640..956M}. WET campaigns have observationally borne this out. More than 5 days of nearly continuous monitoring of the hot DAV G226$-$29 revealed just one independent pulsation mode \citep{1995ApJ...447..874K}, whereas the cooler DAV G29$-$38 has more a dozen modes of relatively high amplitude \citep{1994ApJ...436..875K}. In fact, G29$-$38 illustrates the challenges faced to performing asteroseismology of cooler DAVs: although the WD exhibits at least 19 independent oscillation frequencies, there is significant amplitude and phase modulation of these modes, which change dramatically from year-to-year \citep{1990ApJ...357..630W,1998ApJ...495..424K}. Another excellent example of this complex behavior is the cool DAV HL\,Tau\,76 \citep{2006A&A...446..237D}, which shows 34 independent periodicities along with many oscillation frequencies at linear combinations of the mode frequencies. The complex mode amplitude and frequency variations are likely the result of longer-period pulsations having much shorter linear growth times, increasing the prevalence of amplitude and phase changes in cooler DAVs with longer periods (e.g., \citealt{1999ApJ...511..904G}). The {\em Kepler} mission has already uniquely contributed to long-term distinctions between the handful of hot and cool DAVs eventually found in the original pointing. The longest-studied by {\em Kepler}, the cool DAV ($11{,}130$\,K) KIC\,4552982 discovered from ground-based photometry \citep{2011ApJ...741L..16H}, shows considerable frequency modulation in the long-period modes present between $770-1330$\,s (Bell et al. 2014, in prep.). A much hotter DAV was also observed for six months, KIC\,11911480 ($12{,}160$\,K), which shows at least six independent pulsation modes from $172.9-324.5$\,s that are incredibly stable and evidence consistent splitting from a $3.5\pm0.5$\,day rotation rate \citep{2014MNRAS.438.3086G}.