time calculations

I was looking for the best way to create time calculation in my cubes. Besides using the "add time intelligence" option of BIDS (I use 2008) I found arounf a different technique which implements a "shell dimension". Pro of such technique is that you do not have many new measures for each "regular" measure of your cube but just one dimension working with any measure.
In my case, I would likely have new dimension time related rather then new measures so everytime I would need to manually add clculated member for each hieararchy of my new time related dimension.

In case you are familiar with the "shell dimension" solution, which are the pro and cons of both techniques?
Thanks
Nicola

for reference shell dimension

The "shell dimension" as described is great because some OLAP browsers won't allow you to put attributes from the same dimension on both the X and Y axis, so if you wanted to see time along your X Axis, against Current and YTD on the Y axis, these tools don't let you.

FYI, Darren Gosbel has also written around this. He called it the Mode dimension if you wanted to Google it.

I have a SS that has hours worked by day. I need to get a delta for the over or under 8 hours for each day.

So if in column J i have an entry of 8:15:00 i will get a delta of 15 minutes over for the day. Likewise if I have 7:45:00 in column J I will get -15 minutes for the day. This should be simple but I am having issues figuring out what formula/function and what cell formatting to use. The SS comes to me already formatted (h:mm:SS) for the totals.

Thanks in advance.

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