I don't know of any way to display the call history any different. I have never seen answering to change or edit the way calls are displayed. Maybe a Play Store app can???
When looking at the call history, tap on the clock symbol on the far right hand side for each individual call, and it will list the actual date and time of the call as well as the length as you requested. Unfortunately on the full call log showing all the different calls, it does parse them out the way you mention. I don't believe there's anything we can do to change that information, but I believe it was Google's opinion that accuracy on that screen was not as important and would actually be a waste of resources whereas you can look at the accurate date and time for each individual call as I've mentioned.