No it doesn't work turn off everything but buffet and trim . Turn your plane until screen shakes . Describe your stick actions . If you can't feel the buffet effect from being on the edge of the envelope FF is worthless . The other stuff is meaningless . The advantage of FF is that you process info faster tactily then visually .
ok, let's clarify some stuff:
forces:
trim - force needed to move stick. low trim = floppier stick, high trim = stiffer
stall - low speed shuddering
buffet - high speed shuddering
<edit> these effects are accompanied with visual screen shudder, which occurs at the same time as the FFB is felt. these screen shudders are the non-ffb(ers) clue to the edge, so makes sense they occur at the same time, and not one before the other. </edit>
now i've tested my stick/forces every which way. and they all work as described. disabling one or the other removes that FFB effect from the experience.
neither stall nor buffet forces we feel with FFB sticks can begin to compare with the tactile sensations of actually being in a real plane.
having said that, in regards to buffet kicking in when it's "too late" to escape the terminal dive without resorting to trimming the elevators, you have a point. perhaps the buffet should kick in a sec or 3 before you hit the control lock... easily code-able? i dunno. in a sense the buffet FFB is mere hand candy.
i guess it's a matter of finding the line between normal engine/turbulence and compression. we're getting the compression FFB, not the normal high speed airframe "feel." by all accounts compression effects came on unexpectedly and by then all a pilot could do was whatever he had to survive.. or not.
i'm a little confused why i would expect to feel buffet flying around on the edge.. well, we do, but it's the "stall" buffet force. and it works very well for me... i guess it was an easier physics to code than compression buffet.
what exactly are you wanting? if you're talking more stall than buffet forces, perhaps you have them set too low or too high? too low and u miss it and stall... too high and it's so assertive in the effect that you can still lose it.
i found stall and buffet to work well for me set around 20-30%, while trim 50 - 100%.