An addition is needed in the preferences panel: the ability to turn off the automatic changes to the 'operation' in the dialogue box.
It is assumed by the program, for example, when you extrude a profile and the object happens to intersect another that a cut is required so it automatically changes the operation from 'new body' to 'cut'. However more often than not, a 'cut' is not what is required but rather a 'new body'. It should be my choice and not the programs choice. When the model is heavy this becomes more of an issue because the program switches to 'cut' then is calculating the 'cut' as you are sizing your extrusion for example and it severely slows down the operation. Whereas left as 'new body' the calculation is much much faster.
I realize that this kind of automation is supposed to help but it really doesn't in this case. Many times you think a new body is going to be created because it says 'new body' by default, but later find out you performed a cut or join, then have to go back and correct it.
Please add the option in the preference panel to turn off automatic changes to the 'operation' in dialogue boxes.
