I went a month with them and nowhere was it advertised that they block tethering…
So a word of caution before you decide to spend a lot of money for a slow network that limits your use - this also applies to Optus prepaid resellers such as Woolworths, Savvytel, Virgin, Amaysim, and more.
The only other choices in Australia are Vodafone (slow, buggy, limited connectivity) and Telstra (expensive, lack of 'freebies')
For iPhone? cause if it's for Android, Woolworths actively promote the Tethering feature of their handsets!
iPhone tethering can be unlocked if you jailbreak the phone.