What's wrong with the blending?

Hi (new to the forum),

we know that blending is slow in flash, ok, but there is something too strange though.

I made three tests to profile the blend and I found out something quite weird;

being sure that the movieclips on the screen were contiuosly rendered and always visible, I setup the three tests in the following way:

In the first test I had 25 pretty simple vector shaped MCs with the blendmode ADD setup and the frame rate was relatively good.

In the second test I had 25 pretty simple vector shaped MCs with the blendmode ADD setup and the frame rate was poor.

In the third test I had 25 pretty simple vector shaped MCs with the blendmode ADD setup and the frame rate was relatively good again.

What was the difference between the tests? Precisely the space between the movieclips.

In the first test the movieclips were never overlapping

in the second test the movieclips were overlapping

in the third test the movieclips were exactly on the same position.

Now, that’s for me is quite odd, is there somebody out there that knows what is going on?

Thanks!