I am confused about the MOSFET parameters. Consider a depletion N-channel MOSFET. Suppose the gate-source (Vgs) threshold is Vth = -2V, in its off position. Suppose we have not reached the threshold and we are at Vgs = -1 V. This means that the MOSFET will conduct when a voltage Vds is applied (let Vds = +3 V to drain). There also exists the pinch-off voltage Vp beyond which saturation occurs.
Actual datasheets seem to suggest that Vth and Vp are independent of each other, yet I have seen statements such as Vds > Vgs - Vth. I am not sure if Vp = Vgs - Vth, as some discussions seem to suggest.