Trim/Extend edge mode -Strange

I have just fould the trim/extend to implied lines (edge mode).For extending this is brilliant, but for trimming its a DISASTER.When using trim all (wich is very usefull) this will trim to any implied line in the drawing (useless). Same applies to extend but extend is usually used with defined lines.This is no real bug it works the same in BigBrother2000.The way it should work is that whenever trim/extend all is invoked, implied lines should automaticly be turned off.Correct me if Im wrong (usually there is always someone who has made use for useless functions).