As I've said, we had a certain amount of capacity with a certain amount of usage on the network, everyone was happy, shaping was minimal. Usage spiked around the time of iOS 7's release, and we felt (justifiably so) that usage would settle and we would have sufficient capacity for the usual level of demand. However, even though demand did decrease, it did not do so significantly enough for us to go back to the shaping we had previously. When it became clear that usage would be be decreasing further, began emergency planning to see what short and long term options would be available to us.
Until we can implement some significant changes to the network, shaping is the most effective way to manage the network so that real tim priority services are preserved, and clients still get the maximum bandwidth benefit when there is less demand.