I don't see the problem with minimum fuel while the destination is covered with TS. It just means the chance is higher you have to divert. It only means that.
Is it smart? No, not in my opinion, since diverting costs more money then 30 minutes of extra fuel. But it doesn't make it unsafe, as long as you keep planning to land with 30 mins of fuel left.
It does limit your options and makes for more work though..