That's because the new fertility checks adds both actors fertility and divides it by two which makes more sense than the way it used to be.
Don't know anything about the animals never checked any of the scenes for them not my thing.
The threesome impregnation is little more complicated as it also takes precum into consideration. Which is why pulling out even in real life doesn't work as the most potent sperm is actually in the precum.
No, I get why the pregnancy works as it does, I just don't like it. Unless I was into a gambling aspect, I wouldn't go through the effort to get max fertility unless I wanted to always do it. I don't know what the old way was, so I can't comment on that, but for random girls, like during the bachelor/bachelorette threesome, if you fail because they have a fertility of 0, you don't get another shot. I would pull out if that was the case. Which is actually how it is in the threesomes. If you don't blow in the vagina, there is no baby. Unless you mean that multiple creampies adds to it, or rather the first shot is the most likely, you would need to explain. My point on the threesomes is that it is backwards who gets knocked up.
I wasn't searching for the beast stuff, it was just one of those random events that I assume determines how often, or even if you get them. I popped it up after I had the issue with the ravagermod to see if all of the mods were affected by the update.