I thought that was a little odd, too...and also, if she isn't in the bed or the house, why would you have to count on droplets in the sink to tell you she isn't home...
I am certain the police and now the FBI asked him this question immediately, to determine if she actually left the house: how exactly did he know what she had done that morning? I would have done precisely the same thing, for my children, looked around the sink - they leave a small little mess with water and wet toothbrushes, which today I am actually finding endearing. I heard longing in his voice, like he wished she had left those droplets around that sink the day of the interview.
I am also thinking that, if there is suspicion of a hit-and-run situation, the authorities and family would be giving out less information, keeping the idea of abduction out there, while they quietly question and canvas the town, to put the perpetrator at some ease.
I appreciate what others have said about the running shoe as a decoy or deliberate message. I lost one once during a track meet in high school and it never happened again while I was a jogger. Especially as she had lost a part of a leg bone to cancer(sorry, I do not know which one) it makes me think she was probably fastidious about securing her shoes, especially as most rural roads have gravel this time of year from sanding, etc. My first thought was that she had thrown it herself, as a sort of clue. The fact that we have seen only the tread disturbs me. I am sure we don't have all the evidence the authorities do about that shoe.
I also think it is well within the realm of possiblilty that a 43 year old woman could be a target of sexual predation. I am reminded of the well publicized abduction and murder of Kristi Cornwell. Rape is a crime of violence against women, not just younger women, all women. That is yet another reason the crime is so frightening - half of us are at risk, from the minute we are born, and we don't outgrow it.
It is 15 degrees Farehneit in Sidney right now, with a wind chill of 3 degrees.