I just recently wanted to check (coming from 3rd and 4th edition) if strategy rating had any effect in the game. So, having my handy (and ultimately very cool) PDF version I used
ctrl F (aka Find function) to search for "strategy" only to find that not even ONCE did the rule book even MENTION strategy.
Just a little irony there... also:
ERGO
40k tournaments should be banned for people under the age of 18 (or 21 in some areas) since the game counts as gambling