Additional performance related timing data required in the audit log on a per-card basis

A change that I would love to see in audit logs is a start time and an end time for each card.  The current way of showing timings at the card level – with a “TimeStamp” at each card – is very confusing.  I get the idea that the TimeStamp means different things if it's an input card or an output card – on input cards, it seems that it's a start time (the TimeStamp of input 1 always matches the StartTime at the beginning of the log), but the TimeStamp for output cards is almost certainly the end time, as it jumps on cards that process more data.

For example, a map that has a large amount of input, and where Target 3 does a lot of work on that input, seems to look like this:

          StartTime = 12:00:00
          Source 1      TimeStamp = 12:00:00
          Target 1       TimeStamp = 12:00:10
          Target 2       TimeStamp = 12:00:10
          Target 3       TimeStamp = 12:00:30

That's really confusing.  Did the 10 seconds elapse while processing Source 1 or Target 1? Or was it spread out between the two? Was the 20 seconds spent in Target 2 or Target 3? It would be much easier if it looked like this:

          StartTime = 12:00:00
          Source 1      StartTimeStamp = 12:00:00 EndTimeStamp = 12:00:10
          Target 1       StartTimeStamp = 12:00:10 EndTimeStamp = 12:00:10
          Target 2       StartTimeStamp = 12:00:10 EndTimeStamp = 12:00:10
          Target 3       StartTimeStamp = 12:00:10 EndTimeStamp = 12:00:30

…or this:

          StartTime = 12:00:00
          Source 1      StartTimeStamp = 12:00:00 ElapsedSec = 10
          Target 1       StartTimeStamp = 12:00:10 ElapsedSec = 0
          Target 2       StartTimeStamp = 12:00:10 ElapsedSec = 0
          Target 3       StartTimeStamp = 12:00:10 ElapsedSec = 30