It could but it doesn't answer the question as to WHY you're putting your weight on your rami instead of on your ischial tuberosities. I guess an experiment would be to 'tuck tail', consciously tucking your pelvis and sitting on your ITs... seeing what that does to the rest of your posture. If your stem is too long/handlebars too far forward, you could be compensating by rocking your pelvis forward to reach. There should be a gentle kyphoid curve to your back when you're in proper position, and you should (theoretically, anyway) be using your core to keep yourself in that relaxed-elbows, kyphoid-curved, pelvis-tucked position.

Brooks could encourage you to sit on your ITs if only because if you tipped the saddle up and it didn't have a cutout, and you tried to rest your weight forward, you'd be singing soprano in adult language.

The up-on-rami seated position is generally for those who have absolutely no recourse because their handlebars are SO much lower than their saddle, like on this bike:


I hope that helps.