From:  Michael Gibson
3806.4 In reply to 3806.1 
Hi Ed, also another thing is that MoI's Trim workflow allows for another function which can come in handy which is being able to specify "Pieces to keep" or "Pieces to discard" when you're selecting the fragments. The AutoCAD method is limited to only being able to specify pieces to discard.

Here's an example - here I am trimming a sphere by a whole bunch of little cutting pieces:

The way MoI's Trim workflow is set up, when you get to the stage where you are clicking on the fragments, there is an option for which mode you want to use, whether the pieces you select will be discarded, or whether the pieces you select will be the ones that are kept and unselected ones discarded, it's here:

So for example with this case here instead of picking all those little pieces after switching Mode = Keep, I can just pick the one big piece instead like this:

And get the same result as if I had picked all those little pieces to remove:

This can come in particularly handy with surfaces when the surface is partly submerged in some other surfaces or solids where it is hard to reach all the little pieces that you want to get rid of but the pieces that you want to keep are often larger pieces that are more on the outside of the structure.

It can come in useful with curve trimming as well though when you're working with some larger batches of stuff.

It's another thing that works more easily with MoI's Trim function with having the fragment selection part as a distinct separate stage of the command.

- Michael