  Recent data, added to the ITPA global H-mode database [1] for ASDEX-U [2] and
JET-ILW, reveals that the separatrix density $n_{sep}$ has a correlation with
the H20 factor (Confinement time relative to the ITPA20-IL scaling)[1]. These
trends are analyzed in detail. They are not a result of proximity to the
density limit. The normalized $n_{sepN} = n_{sep} / \bar{n}$ is introduced,
motivated by theory ($\bar{n}$ is the average density). The trends in
$n_{sepN}$ can be understood in terms of the two main mechanisms of pedestal
characteristics -- MHD stability and recently developed theories of gyrokinetic
transport. Careful analysis shows these mechanisms can be distinguished in the
data. The most dramatic improvement in confinement time arises primarily from
reductions in pedestal transport. A new definition of density peaking that
includes core peaking is found to best explain H20 when advanced H-modes are
included: $n_{sepN0} = n_{sep}/n(0)$, the inverse of the total density peaking
from the separatrix to the axis. The highest H-factors are reached by the
confluence of relatively low normalized $n_{sepN0}$ plus high Shafranov shift
or poloidal beta. The importance of these two variables is also theoretically
predicted from recent analysis of the gyrokinetic system, where a constraint
can limit the access of ITG/TEM modes to free energy in equilibrium gradients.
The Plasma Facing Component (PFC) material also shows a strong influence in the
data. This is likely due to the importance of $n(0)/n_{sep}$ to attaining high
H20, in conjunction with the known tendency for tungsten (W) to accumulate with
density peaking and low transport. Preliminary results indicate that
$n_{sepN0}$ might also be important with core ITBs.
