contrast, radial flow has been observed at all energies [@Cheng:2003as] and has been shown to be very sensitive to late time “pion wind” radial pressure gradients [@Bass:2000ib], which continue to blow after the QGP condenses into hadronic resonances.

The observation of near ideal $v_2$ fluid collectivity as predicted with the $P_{QCD}$ together with $v_1(y)$ and other consistency checks (${\bf \rm\bf c.c.}$) conclusively establish the first term in Eq.(1) : $${\rm\bf P_{QCD}}= v_2(p_T; \pi,K,p,\Lambda) + v_1(y) + \;{ \rm\bf c.c.}
\; \; .
\label{Pdef2}$$ Preliminary Quark Matter 2004 analysis of $\Xi,\Omega$ flow are consistent with the predicted $v_2(p_T,y=0,M,h)$ and this information is lumped into the ${\bf \rm\bf c.c.}$ terms in Eq.(\[Pdef2\]). Other data which provide consistency checks of the hydrodynamic explanation of collective flow include the observed $\pi,K,p$ radial flow data [@Cheng:2003as] for $p_T<2$ GeV. In addition, predicted statistical thermodynamic distributions [@Braun-Munzinger:2003zd] of final hadron yields agree remarkably well with RHIC data. Had hadro-chemistry failed at RHIC, then a large question mark would have remained about bulk equilibration in the QGP phase.

QGP Precursors at SPS and Dissipative Collectivity
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It is important to point out, that no detailed 3+1D hydrodynamic calculation [@Hirano:2003hq]-[@Hirano:2003pw] has yet been able to reproduce the rapid 