Openshift ResourceQuota usage rather than reservation?
I am trying to understand how I can utilise the entire of my project CPU quota based on the "actual current usage" rather than what I have "reserved"
You can't. If your quota is on limit.cpu then the cluster admin doesn't want you to burst higher than that value.
If you can get your cluster admin to set your quota differently, to have a low request.cpu quota, and a higher limit.cpu quota, you might be able to size your containers as you'd like.
The other option is to use low limits, and a Horizontal Pod Autoscaler to scale up the number of pods for a specific service that is getting a burst in traffic.