[Trac] working estimation into tickets

[Christopher Taylor]

I personally could see where both would be beneficial.

"Estimated time of completion and "Date of compeltion" are more of a
schedule issue
"Time spent to complete" is more of a accounting/budget issue
"Difference between Estimated and time of completion" is more of a
process improvemen issue (for further enhancing your estimating
techniques)

just my 2c

Respectfully,
Christopher