Moved Observer-lines don't give multiple signals anymore

In prior Minecraft versions the following behavior was really useful and heavily used for flying machines:

If you push multiple observers at once that are in a line (so if the first one updates it will propagate through) you will get multiple powerings of the last observer, because every observer would detect the previous observer changing into the off state.

Now this seems to be broken and only one pulse comes out wich is really sad.