If you can break down his behaviour into rules then in theory at least you could check to see whether it was just luck or he'd somehow spotted a real pattern (meaning the seeding system is broken). That would mean running loads of tests where you ran the betting rules against a long series of bets from multiple sets of seeds.
The problem is, I can't. Here's the most recent betting session, as posted a few posts up from here. I've separated the small (left column) and large (right column) bets out, and tidied up the formatting. I don't see any obvious rules being followed. Do you?
Read as follows: he bet small, saw a win then a loss, then bet 1 BTC and lost. Then he bet 5 more small bets, seeing 4 wins and a loss, then bet 2 BTC twice, losing both. Etc. Those first two sequences follow the "wait for WL then bet big" rule. But the rest of the session doesn't see it happen again at all:
W L 1 lose
W W W W L 2 lose
2 lose
L L W 5 win
5 win
5 lose
L 2 win
L 2 lose
2 lose
4 win
22 lose
22 lose
W 11 win
11 lose
20 win
W 20 win
L 10 lose
10 win
L 2 lose
4 lose
16 lose
L W W 10 win
10 lose
20 win
W 10 lose
20 lose
L L L W W 10 win
10 lose
20 win
10 win
10 win
10 win
10 win
10 win
10 win
10 win
10 lose
20 lose
L W 10 lose
20 lose
W 20 lose
20 lose
W L 20 lose
20 lose
L L L L L W W 20 win
20 win
20 lose
10 win
L 20 win
L 10 lose
20 win
L 10 win
W 10 lose
20 lose
L W W L L L W W L L L W L 10 win
W 10 win
10 lose
5 win
L 20 win
L 10 lose
20 lose
W L 40 win
L 10 win
W 10 lose
20 lose
40 win
10 lose
20 lose
W L 20 lose
20 win
40 win
20 win
20 lose
40 win
W 10 lose
20 lose
L 30 win
W 10 lose
W L 10 lose
20 win
L 10 win
L 10 win
W 10 win
10 win
10 win
10 win
10 lose
20 win
20 lose
40 win
L 10 lose
L L L W W 20 win
20 win
20 win
20 lose
40 win
20 win