Mykan
Oh Wise One
The reason people say it's a joke is that there are lots of ways to use 28 squares to get more than 1 broken rune shard every 7 days.
Any military building or factory will make enough goods or troops to get more than 1 extra broken rune shard each tournament.
Add to that if you do bother to level it the cap of 10 broken shards could see you wasting the collection or delaying it if it is not timed well.