Why the slight increase in win% here? (from poker calculator)

[Kerplunk]

Hi, I was playing around w/ poker calculator. I was wondering why top and bottom pair had a slight advantage to top two pair in the following scenario:

Flop is a[img]/images/graemlins/diamond.gif[/img] j[img]/images/graemlins/diamond.gif[/img] t[img]/images/graemlins/heart.gif[/img]

According to two dimes calculator...
http://twodimes.net/h/?z=662259
pokenum -h ac js - 9d 7d -- ad jd th
Holdem Hi: 990 enumerated boards containing Ad Jd Th
cards win %win lose %lose tie %tie EV
Js Ac 563 56.87 418 42.22 9 0.91 0.573
9d 7d 418 42.22 563 56.87 9 0.91 0.427

whereas...
http://twodimes.net/h/?z=662255
pokenum -h ac ts - 9d 7d -- ad jd th
Holdem Hi: 990 enumerated boards containing Ad Jd Th
cards win %win lose %lose tie %tie EV
Ts Ac 589 59.49 392 39.60 9 0.91 0.599
9d 7d 392 39.60 589 59.49 9 0.91 0.401

So, why the slight bump in win% for AT over AJ? don't quite see how having another T in play helps the other guy in this case, but I'm probably missing something obvious.

Thanks for yur help

[Nick M]

one less diamond for 97 to hit. The 10 of diamonds makes A10 a full house

[Kerplunk]

Thanks!