[QUOTE=Trakhak;23590491

My point was that, even if your claim that the chainring pushes the chain toward the rear derailleur were accurate, which my examples showed it isn't, whatever happens to the lower span of the chain has no effect on front shifts..[/QUOTE]
Well, yeah, it's also getting pulled through the rear derailleur cage by the rear cog, which is being driven by the top span of the chain being driven by the crank. OK, I see what you mean.