If a BWB is a split strike fly,you are simply short a vertical.Im guessing your risk reward is 1 to 1,5 point long a 5 point vertical + short a 10 point vertical,same short strike
I will show some pix later, but a pop in volume does decrease the T-0 line, overtime theta really keeps the T-0 line stable. I have been analyzing the Fall of 2018, Betrix 2015, Volmageddon 2018 and I was amazed how stable the T-0 line is. I will add the test pics here.
Part of the reason I've started this journal was that after watching this video:
I realize I have to be more diligent in documenting my thoughts. I figure this forum would help be accountable to my trading and may be I could add value to somebody on their trading journey