Here are the possible values when you roll a pair of dice. This is the distribution that makes up the BINOMIAL COEFFICIENT and is what he was referring to:
2: 1&1
3: 2&1, 1&2
4: 1&3, 2&2, 3&1
5: 2&3, 3&2, 4&1, 1&4
6: 5&1, 1&5, 4&2, 2&4, 3&3
7: 6&1, 1&6, 5&2, 2&5, 4&3, 3&4
8: 2&6, 6&2, 5&3, 3&5, 4&4
9: 6&3, 3&6, 4&5, 5&4
10: 6&4, 4&6, 5&5
11: 6&5, 5&6
12: 6&6
THIS DOES NOT PREVENT YOU FROM HAVING A BINOMIAL DISTRIBUTION. If we convert that chart above into:
0 - Rolled a 2 or 3
1 - Rolled a 4-12
2: 0
3: 0, 0
4: 1, 1, 1
5: 1, 1, 1, 1
6: 1, 1, 1, 1, 1
7: 1, 1, 1, 1, 1, 1
8: 1, 1, 1, 1, 1
9: 1, 1, 1, 1
10: 1, 1, 1
11: 1, 1,
12: 1
You see how many freaking 1s there are? If you get a 0, you have a MUCH greater chance of getting a 1 on your next roll than a 0. Thats what he was saying.