  We describe large scale structure at high redshift in terms of the Cosmic Web
picture for {S,Lambda,O,H}CDM models: how galactic-scale ``peak-patches'',
filaments and membranes create an interconnected intergalactic medium. The
ideas are applied to our Ly$\alpha$ forest simulations of ``shear-field
patches''. We discuss simulation method and design, resolution dependence, the
statistical combination of patches, UV flux scaling, and whether filtered
Zel'dovich maps are useful. The response to changes in power spectrum shape and
amplitude, and in cosmological parameters, is described. We also show Omega_b
h^2 derived from UV rescaling is overestimated if the resolution is not
adequate.
