This isn't so much a trend as it is a part of internet history.
The use of an asterisk in the word harks back long before the Cat-L list to the early Usenet bullitin boards. (rec.aquaria I think it was at the time).
It started basically as this, an aquarist wrote a long drawn out and quite humorous post about how every time he type p-l-*-c-o (YES, I still believe)

, one of his fish dies...
After several dozen very funny posts back an forth, including if I remember correctly at least one "experimental" thread which supposively "confirmed" it to be true

, the consensus at the time was that the word was not to be typed in this form, lest one of your fish die.
So, techically speaking, you all owe Jools a debt of grattitude for writing this into the code of this board, thereby saving countless little lives in the process
