Because an original splatter just isn't cool enough. This happend when a friend and I where rushing this part of the covenant with the gaus, while another friends was slow with the scorpion. As a result we got the hornets much earlier, so we went just messing around, and watching the scarap inpact before the explosion was there. Then a huge bam came, and the hornet and I got splatterd by the scarap, realy, realy hard. Oh and yea, I shoot through the scarap, flying realy high. =] It was pretty cool.
I've actually done this before once too, except when I did it my xbox froze and it took a while to get it fixed.
At first, I thought the picture was okay. Then I looked at it for a couple more seconds, and I just burst out laughing =P