Nicely done.
I suppose the men from Cutler's lead regiment (76th New York) probably took down a small portion of the fence running along the west side of the Emmitsburg road near the Codori farm, although normally this was a task of the pioneers, who were evidently marching at the rear of that brigade, based on this source:
(J. V. Pierce, 147th New York, National Tribune, April 3, 1884) "... when about half a mile from Gettysburg, there was a call for 'pioneers to the front.' ... The pioneers could hardly throw the fences down quick enough for us. The most troublesome fence was a strong post-and-board fence on both sides of the Fairfield road, near the Seminary grounds."
As the Iron Brigade approached the Seminary, their pioneers were in front, according to E. R. Reed of the 2nd Wisconsin, who "saw our sappers and miners rush for the fence and scatter a length or two in great haste, and we hastily filed left oblique through the opening, and continued the same left oblique through the field" [between Seminary and McPherson ridges]. (E. R. Reed, National Tribune, March 20, 1884)
Reed's account explains how the Iron Brigade approached Herbst woods from Seminary Ridge. Incidentally, the removal of the fence by the Iron Brigade's pioneers was observed by Lidia Zeigler from her vantage point in the Seminary building.