I play both NRL Fantasy, based off NRL stats, and SuperCoach, based off privately complied Stats.
To put it in perspective just how subjective the whole Try Assist thing is, James Tedesco last Thursday against the Cowboys was awarded 4 Try Assists plus 1 Try Contributions in SuperCoach, while NRL Stats only awarded him the 2 Try Assists.
Those are radically different interpretations of the same plays and the same game and just goes to show you how subjective the whole thing can be. There is even a widely held suggestion in SuperCoach that certain players involved can influence what constitutes an identical Try Assist or not, with a media poster boy like Tedesco (amongst others) invariably getting the benefit of 50/50 calls on the SuperCoach stat counts, but that not being reflected in the official NRL stat counts.