Then why does he always get run down when he makes a break or half break. He has acceleration over 10-15m, but then he has no top speed. This is the same way that Nof has been talked about as 'one of the fastest players in the comp - statistically'. Nof has never been fast, he just had decent acceleration over a short distance.
Fast players make breaks and finish them. Lawrence was fast once upon a time, JAC, Saab, Walsh etc. These players are fast. Toa wouldn't be in the top 50 players in the comp for pace. Nof would be in the bottom 5 out of all NRL backs.
Perhaps Toa can develop some speed with more training, but the fact is his body has matured, he's 23 now and has been playing NRL for 5 years. Chances of him developing a new skillset is slim, he is what he is, and that's a capable backup at present. We need two starting quality centres, Naden is a winger too.