Clarify the normalization will fix mixed space use

bip-0039/bip-0039-wordlists.md

@@ -8,9 +8,9 @@
 ###Japanese
 
 1. Users will most likely separate the words with UTF-8 ideographic space.  
-(UTF-8 bytes: 0xE38080) When splitting for validation or joining for generation, replace  
-all instances of ascii space with the ideographic space, and in case of a mixture of space  
-types, also replace just before seed generation.
+(UTF-8 bytes: 0xE38080) When generating the seed, normalization as per the spec will
+automatically change these into normal ASCII spaces. Depending on the font, displaying the
+words should use the UTF-8 ideographic space if it looks like the symbols are too close.
 
 2. Word-wrapping doesn't work well, so making sure that words only word-wrap at one of the  
 ideographic spaces may be a necessary step. As a long word split in two could be mistaken easily