I feel the need to clarify and tweak the information Lisa has provided. The 16% VBAC rate in Australia is the rate of vaginal birth after cesarean in all women who have had prior cesarean surgery. I am not aware of Lisa's source for home birth VBAC stats (Lisa: If you have a published source, I'd love to have it because I'm working on the VBAC chapter for the new edition of Obstetric Myths Versus Research Realities, and, as you may imagine, the safety of out-of-hospital VBAC is a crucial issue), but her 97% statistic represents the percentage of women planning VBACs who give birth vaginally. As you can see, these are different stats. I am not surprised, though, that the rate is higher than that typically found in hospital VBACs, which is in the mid 70 percents. The sole study of VBACs in freestanding birth centers also reported VBAC rates substantially higher: 87% overall and 81% in women with no prior vaginal births. 

Lieberman E, Ernst EK, Rooks JP, et al. Results of the national study of vaginal birth after cesarean in birth centers. Obstet Gynecol 2004;104(5 Pt 1):933-42.

Also, I have never seen a report finding that raised maternal pulse rate was an indicator of scar rupture. As Amy wrote, severe fetal heart rate abnormalities is the most reliable sign, although it does not appear that picking those up via continuous electonic fetal monitoring has much effect on improving outcomes.  

Epidural analgesia is not contraindicated in VBAC labors, although it has drawbacks. Labor augmentation--intensifying labor with oxytocin--is often required with an epidural, and augmentation is associated with an increase in scar rupture, although the risk almost certainly would depend on how aggressively oxytocin was being used. In addition, epidural analgesia occasionally causes fetal heart rate decelerations, which might erroneously lead caregivers to think that the scar has given way.

Finally, I cannot agree that every woman is an "excellent" candidate for VBAC, although I will happily argue that there are few cases where the risks of a planned VBAC outweigh the benefits and that no one should have the right to decide that a woman should have cesarean surgery, planned or during labor, other than the woman herself. That aside, Robin happens to be an optimal candidate for VBAC by virtue of having had multiple prior vaginal births and a nonrepeating indication for her prior cesarean. As it happens, I have just finished reading the set of papers on the effect of prior vaginal births, and not only is the likelihood of VBAC the highest of all, as Amy wrote, but the likelihood of scar rupture is also reduced.

-- Henci