If this was fixed in 4.3, then the wiki and refguide should note that:
As of Solr 4.0, REALOAD performs "live" reloads of SolrCore, reusing some existing objects. Some configuration options, such as the DataDir location and IndexWriter related settings in solrconfig.xml can not be changed and made active with a simple RELOAD action.
Starting with Solr4.0, the RELOAD command is implemented in a way that results a "live" reloads of the SolrCore, reusing the existing various objects such as the SolrIndexWriter. As a result, some configuration options can not be changed and made active with a simple RELOAD...
IndexWriter related settings in <indexConfig>
SOLR-3592 for more background.
I would also note that the wiki page is another candidate for full migration to the new refguide since the refguide is essentially a cut and paste of the wiki page.