diff --git a/AFNetworking/AFHTTPClient.m b/AFNetworking/AFHTTPClient.m
index 354aa21..6f0273a 100644
--- a/AFNetworking/AFHTTPClient.m
+++ b/AFNetworking/AFHTTPClient.m
@@ -102,14 +102,6 @@ static NSString * AFBase64EncodedStringFromString(NSString *string) {
 NSString * AFURLEncodedStringFromStringWithEncoding(NSString *string, NSStringEncoding encoding) {
     static NSString * const kAFLegalCharactersToBeEscaped = @"?!@#$^&%*+=,:;'\"`<>()[]{}/\\|~ ";
     
-    /* 
-     The documentation for `CFURLCreateStringByAddingPercentEscapes` suggests that one should "pre-process" URL strings with unpredictable sequences that may already contain percent escapes. However, if the string contains an unescaped sequence with '%' appearing without an escape code (such as when representing percentages like "42%"), `stringByReplacingPercentEscapesUsingEncoding` will return `nil`. Thus, the string is only unescaped if there are no invalid percent-escaped sequences. 
-    */
-    NSString *unescapedString = [string stringByReplacingPercentEscapesUsingEncoding:encoding];
-    if (unescapedString) {
-        string = unescapedString;
-    }
-    
 	return [(NSString *)CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, (CFStringRef)string, NULL, (CFStringRef)kAFLegalCharactersToBeEscaped, CFStringConvertNSStringEncodingToEncoding(encoding)) autorelease];
 }