Particle Speed material node Only works in Shader Model 5

I’m attempting to control panner speed with particle speed. Amazingly this works just fine on a mesh particle, but only in Shader Model 5.

For testing I created a simple unlit material with particle speed piped into emissive (with a division due to excessive particle speed). The particles are white as they move and fade to black as they slow down due to drag. When I change to any other renderer the particles stay black. This behavior is true of standard or mesh particles.

Is this intended functionality?

Thank you,

Chris

In case that is def. a limitation, is particle relative time or the parameter node available?
Because you could “fake/smoke & mirror” the effect in a worst case scenario.

that said, why didnt I think of using particle speed for that hehe.