Good Strategy in large MTT's. I try to do the same, but it takes discipline. If often not patient enough.
To add to this strategy: 1. I play numerous good drawing hands at the first 1, 2 or even 3 levels. I run the risk of investing too many chips early, but can usually hit a big hand(s) to make it worthwhile.
Also, I think it is mandatory to gradually and continually increase your range, steal blinds and bluff in later levels. More risky, but necessary to make the final table.
There are a several great MTT threads in the CC Strategy Articles. I would encourage you to read them.