I've never heard it from LE or in the media, but
@Charlot123 and I have speculated a lot on it quite a bit in the past.
For me, the RL affidavit is interesting in two respects. The redacted area in one spot is suspected to be stating that the murder weapon is a bladed weapon or knife. Killing with a knife, even when not including the mental aspect, is difficult. Second, the affidavit states there was no sign of a struggle. With two victims. That suggests to me that this killer did this VERY quickly. And who receives training in that sort of thing. Soldiers and Marines.
What gives me pause is that LE has knowledge of the crime scene and the autopsies. And I would think it would be more obvious to them and they've never said any such thing. Of course, LE has been tight lipped about this from the get-go so maybe they just haven't said.