Dave Smith Instruments SYNTHESIZERS

Does anyone know if it is possible to crossfade between oscillators 
(say, 3 & 4) using the LFOs? I've tried, but so far I've only gotten 
what sounds like the rise and fall of one osc, followed by the rise 
and fall of the other with no overlap whatsoever.

I have been able to get the sound I'm looking for by using Env3 to 
raise the level of an osc while simutaneously using Env3 negatively 
(via a mod bus) to bring down the level of another osc. But obviously, 
this is not loopable. Is there a way to do this with LFOs?

My overall goal here is to get some Prophet VS-style morphing 
textures, but I'm just not sure it is possible with the evolver.