There's a 40-50% chance you're right that we will temporarily touch $25/share. As you know, this would bring us to 8x earnings, a record low for a well-financed utility.
The long-term investor cannot afford to take the risk that we miss $25/share.
According to a study by Oak Ridge National Laboratory, Exelon's reactor operating costs are around $15-20/MWH. Combined cycle turbines spend $5/MWH alone on maintenance. Generously assuming 50% efficiency and $3/mmBTU, the natural gas producers are running operating costs of at least $25/MWH, so Exelon's nuclear reactors have a $5-10/MWH edge over natural gas. We produce 262 million MWH per year, so the floor on operating income for the generating portion of the utility is around $1.3- $2.5 Billion. (This does not include distribution and transmission, which probably generate another $1-2 Billion).
Meanwhile, our bonds carry about $500 million/year of interest. You do the math.
The ICC will grant ComEd a significant rate hike next year if we start trading at the book discount you suggest.
So we may touch $25 for a short time, but fundamental pressures will move us back up to the thirties fairly easily.