GDG- Gettysburg The second day

[James Cameron]

<< A point frequently overlooked when attempting to understand the
breakdown  of the en echelon attack on July 2nd is that Posey did not
just half-heatedly support Wright's  attack on purpose; the federals
located in the Bliss Farm buildings on his flank would have been fatal
to his brigade if he had ignored them by advancing with Wright. He HAD
to send half of his brigade to deal with them.
He had no choice.

                        Pres  >>

I think much of it comes down to Anderson not being set up to make a major 
attack of his own.
The idea of the attack being made en-echelon comes, I believe, more from the 
way it was actually mounted, than from how it was originally planned.  In 
the original plan, McLaws was to attack up the Emmitsburg Road, supported by 
Hood.  We don't know exactly how Hood was to have done that, but I've never 
seen anything to state specifically that the two divisions would attack en 
echelon to one another, or in sequence.  Anderson, for his part, was to 
support the attack as it reached his sector, driving the AOP in toward the 
town.  In other words, support an attack already pretty much a success, not 
make one of his own.  His division wasn't deployed in the depth Hood and 
McLaws were, which meant his brigades had no second lines behind them, ready 
to come up in support, or, exploit any success.

Jim Cameron