I haven't read this entire thread, but it's only neutral in the first moment[g-mean]. You cannot neutralize gamma with shares unless you dramatically overhedge delta. You're short the backspread and momentarily flat deltas and gammas.
The position accumulates deltas/time. IOW, the risk of a decline in the stock will hurt the short backspread as well as the stock hedge. You've no business trading this position unless YOU can answer the questions posed.
To add: the vega and gamma risk reach their nadir at the long strike, of course.
riskarb
The position accumulates deltas/time. IOW, the risk of a decline in the stock will hurt the short backspread as well as the stock hedge. You've no business trading this position unless YOU can answer the questions posed.
To add: the vega and gamma risk reach their nadir at the long strike, of course.
riskarb