The title may surprise you, but you can’t ignore the statistics.
Every sector shows its strength depending on  the economy, government policies and supply/demand.

Here is my observation on Banking sector:
From 2003 to 2010, Banking sector  has been doing well in Q3 except 2002.
Using 2003-2010  NSE-Bankex data
Average return in Q3: 21%
Minimum return in Q3: 9.4% (2004)
Maximum return in Q3: 43%  (2006)
Number of -ve return in Q3: 0

Series of Q3 return is  all positive values.

Bankex Index  series  from July to September (Assuming 1st value of the July month as 1)

Bankex return for Q3:
 

Year	2003-Q3	2004-Q3	2005-Q3	2006-Q3	2007-Q3	2008-Q3	2009-Q3	2010-Q3
Return(%)	17.94%	9.44%	25.64%	43.24%	16.61%	17.03%	13.89%	31.26%

 Note: 2002 Q3 return of Bankex was negative (-6% ).