Originally Posted by
Makuul
Once you hit level 64, you get a Spirit > Hit conversion ability that treats all Spirit as Hit rating at a 1:1 value. So all the int/spirit spell leather you're wearing all of a sudden converted into Int/"Hit" while still retaining the Spirit stat (should you have a Resto offspec, say) to function normally. However, as you level, each successive level requires an increase in your hit to stay at a static percentage. So, say, it takes 800 Hit/Spirit to be hit capped (when you never have a miss percentage) at level 64 (totally made up number, I have no idea what it actually is), as soon as you level to 65, it may take 825 to stay capped. This is to account for gear inflation as you level.