No, definitely not ianbakewell. Has to be a lie.
The funny thing is that transaction d23b8ec28b10902d5882acc6e2a96418698fa571032bfa459ba417f9929a4e04 paid out 4 BTC before any 2 BTC deposit to the game address ever happened. So he's not even doubling a pretend deposit to himself - he's doubling nothing.
Here's a summary of the 2 bets of 2 BTC and the 2 doubles to 4 BTC in the order they happened:
doubled nothing to 4 BTC:
2012-09-11 22:54:00 block 198361 d23b8ec28b10902d5882acc6e2a96418698fa571032bfa459ba417f9929a4e04
inputs outputs
127dNjGRVqzW8tcpTjitmF3GqtXHoiodLc (6 BTC) 1HJDteSfRWud1hiWR75iDNYbQUffmo5Lm 2 BTC
1CyKTdcEHjWtD9FuamThfQA2cjbHvYQnzy 4 BTC
bet of 2 BTC
2012-09-12 08:57:46 block 198415 083bc9301876e4340abb9ae8af5c49c1a084995a110d671431c7c5484287af72
inputs outputs
17hvZSX8rxn4oqWHvsWNd6BNq8jTftTvMj (5.5 BTC) *13pLHUm8gPEN5H4xvTg8pqFHcr24ywzY1Z* 2 BTC
17hvZSX8rxn4oqWHvsWNd6BNq8jTftTvMj 3.5 BTC
ian's bet of 2 BTC
2012-09-12 19:09:52 block 198486 5ebbb89198062454c20bb24fefca4bfd2b1bcf142b67fa0f2689af832280717b
inputs outputs
1KvByyfswhphncQ2uDo29WjX82DrdW2zU9 (0.007 BTC) 15BASR3sz4N6aTrTTaNKrZd5Po9eWmrjCr 0.01 BTC
114kWBPqiboAKcb4Ms65ZrVHcP1s1jFEXG (0.004 BTC) *13pLHUm8gPEN5H4xvTg8pqFHcr24ywzY1Z* 2 BTC
12ytu2WEiB9kxbSQLQzq1fhJFDRwGVp82J (0.012 BTC)
1QCPDfLPK95saavsZokCAuzMiCriNrmfpV (1.9565 BTC)
1Kia3NFWjyJNW4kFXtRHQpBRM2jDxyfmk (0.0095 BTC)
1F6DJCG6SGvhsh72Ca1y448wEkPsRpTa4U (0.0095 BTC)
13JXvcqXXsFJmUJHaoBZJLQKCVxG9Pffmz (0.0055 BTC)
1FrcytRVednQsBLqno7WaGxJFMfQ91NENx (0.007 BTC)
doubled ian's bet to 4 BTC:
2012-09-12 22:34:52 block 198520 062a48f0baff05c3ed09fbb0f7637f1d17619f21e7c9a366c5f2dcd8c5014839
inputs outputs
1CyKTdcEHjWtD9FuamThfQA2cjbHvYQnzy (4 BTC) 114kWBPqiboAKcb4Ms65ZrVHcP1s1jFEXG 4 BTC