minor documentation tweaks

Makefile

@@ -2,7 +2,9 @@ KFVER=129
 
 doc:
 	@echo "Start by reading the README file.  If you want to build and test lots of stuff, do a 'make testall'"
-	@echo "but be aware that 'make testall' has dependencies that the basic kissfft software does not"
+	@echo "but be aware that 'make testall' has dependencies that the basic kissfft software does not."
+	@echo "It is generally unneeded to run these tests yourself, unless you plan on changing the inner workings"
+	@echo "of kissfft and would like to make use of its regression tests."
 
 testall:
 	# The simd and int32_t types may or may not work on your machine 

README.simd

@@ -1,4 +1,5 @@
-If you are reading this, it means you think you may be interested in using the SIMD extensions within kissfft.
+If you are reading this, it means you think you may be interested in using the SIMD extensions in kissfft 
+to do 4 *separate* FFTs at once.
 
 Beware! Beyond here there be dragons!
 
@@ -29,7 +30,8 @@ Search on "SIMD alignment" for more info.
 
 
 Robin at Divide Concept was kind enough to share his code for formatting to/from the SIMD kissfft.  
-I have not run it -- use it at your own risk.
+I have not run it -- use it at your own risk.  It appears to do 4xN and Nx4 transpositions 
+(out of place).
 
 void SSETools::pack128(float* target, float* source, unsigned long size128)
 {

TIPS

@@ -21,7 +21,7 @@ Speed:
 Reducing code size:
     * remove some of the butterflies. There are currently butterflies optimized for radices
         2,3,4,5.  It is worth mentioning that you can still use FFT sizes that contain 
-        these factors, they just won't be quite as fast.  You can decide for yourself 
+        other factors, they just won't be quite as fast.  You can decide for yourself 
         whether to keep radix 2 or 4.  If you do some work in this area, let me 
         know what you find.