Extents and query performance

Recently I was adjusting a performance test, trying to keep it in a reasonable amount of time (for a test) and at a time one of the querys started to take much less time than before. The people that were doing the test told me that the only change made was in the extent size of the table involved in the query. Before it had a first extent size several times the size of the table. After the adjustment, it was set with a first extent very close to the size of the table. Now my question: Could this change in the extent size be the cause for the performance increase, or would it be that with a smaller extent the table was created near the other tables involved in the test, causing the seek times to be smaller? Comments please, and thanks. --