ELiminate 'L_shift' as a parameter?

[smwesten-usgs]

Somewhere along the way, 'L-shift' was introduced as a parameter in order to allow parameter estimation to take place by 'shifting' the Kcb curve relative to the planting date. While this is potentially nice, there is no real reason to have it, since this can be done external to the model without introducing a 'shift' parameter. Confusing and potentially undocumented?