Making sure that private property is properly signed is of utmost importance. Paying particular attention to the TPA sect 2(1)(b),it's required the owner or his/her agent (as defined under The Act) must first advise the offending party to immediately leave the premises when the property is not clearly marked or fencing and signage requirements aren't met or if the cultivation conditions aren't immediately apparent.
Reading statements from "the regs" booklet is a whole world different than knowing how the various Acts read and understanding case law. Precedents that have been set from time to time by the Courts governing those Acts is really the only time someone can say they actually "know the law." Mistakes can be embarrassing and expensive.