If I'm an offensive coach calling plays I'd hope they crash hard to the playside as well. As you said the bootleg off the zone run action would eat the defense alive. Also I'd start running the end around off the zone run action and I'll also fake the end around to force the defense to play honest on the backside. Controlling the backside of the defense is why the zone read from the shotgun is so popular now. You can base your entire offense off the inside and outside zone running game. In my opinion Glen Mason and Minnesota are probably the most effective zone running team in the country.