TL;DR – Comparing within the same tier of card (tested with Diamond cards, I think it will be similar with Sapphires and Emeralds), all Halves are much faster than all Backs, no matter who the back is, including some of the fastest players in rugby league like Hamiso Tabuai-Fidow. Screenshots at the end of the post.
Now that Skillset 3 is available to look at on Pro Team cards, we can actually see the Sprint Speed of our players instead of just blindly following the Movement (MOV) rating on the face of the card. This MOV rating is also very misleading as I don’t feel it takes into consideration the Sprint Speed value at all.
I’ve always felt like my Backs get caught so easily on a line break, but if the Halves make one, they seem to fly through and never get caught. After looking through some of the high rated diamond cards, it seems as though Halves have been given the highest tier of average sprint speed, with Backs on average a little bit lower than that, and Forwards being the lowest. So the feeling of the ultra fast Halves speed wasn’t just placebo! 
This may have happened accidentally back when the Forwards speeds were rebalanced (nerfed because Forwards were way too fast 
) and the Backs somehow also got rebalanced as well, or maybe the Halves got swapped with the speed that the Backs were meant to get? I feel like there is a mistake somewhere because it’s pretty consistent and noticeable across-the-board, and I feel like it’s worth a look into please Big Ant. As I don’t think Halves in general across the board should be faster than Backs in all situations.
ALL Diamond rated Halves (5/8, HB) have a Sprint Speed value in the 90s, ranging all the way up to 97 Sprint Speed on the 94-Rated Diamond RL Elites Cameron Munster 
! This is regardless of the MOV rating shown on the front of their card (92 HB Mikey Lewis having the lowest MOV rating of all the Halves at 85, yet still having 91 Sprint speed).
Whilst NONE of the Diamond rated Backs (FB, W, C) even reach into the 90s for Sprint Speed, all of them have their Sprint Speed in the 80s, this includes 93 Diamond RL Elites Hamiso Tabuai-Fidow (Only 87 Sprint Speed), and we all know how fast he is!
One of the Backs, that just released today, 95-Rated Diamond Team of the Week Peta Hiku has a 96 MOV rating, yet none of his stats within Skillset 3 are even at or above 96, and his Sprint Speed is only 88. So again, slower than every single Half in the Diamond tier with such a misleading MOV rating.
There is only 1 exception to all of this, and there is a reason for that exception, which only further backs up my point about Halves somehow getting much higher Sprint Speed than the other position groups. The exception is 93 Diamond Power House Nick Meaney. He has whopping 96 Sprint Speed and he is a Centre, BUT when he was initially released in the game, his position was a 5/8. Then, a few weeks and patches later, he was changed to a Centre. So he got the speed boost that all the Halves seem to get when he was initially released before transitioning to a Back via a patch and keeping those old Halves-boosted stats.
If you’ve read this far, then a huge thank you to you! I know it’s a big wall of text.
Please let’s get Big Ant to look into this in case it was a mistake that’s gone unnoticed because we couldn’t see the different Sprint Speeds of all the cards until Skillset 3 was added to the card information screen.
I’ll leave some screenshots of different examples below.
A few Diamond rated Halves showing Sprint Speed in the 90s – Cameron Munster is the fastest player in the whole game I have seen so far – All other Halves searched on the Auction House but not shown in this post also have a minimum of 91 Sprint Speed
A few Diamond rated Backs showing Sprint Speed in the 80s – Includes Hamiso Tabuai-Fidow, who is arguably the fastest man in rugby league, and the 93 Nick Meaney who does have 96 Sprint Speed BUT he was a 5/8 when released. Also shows Peta Hiku with 96 MOV but no individual stats even reach 96, and a Sprint Speed of only 88 – All other Diamond rated Backs searched on the Auction House but not shown in this post also have a maximum sprint speed value in the 80s
Diamond Power House Joseph Tapine (Prop – 86 Sprint Speed) is FASTER than the above 94-Rated with 94 MOV Diamond Power House Stephen Crichton (Centre – 84 Sprint Speed). Joseph is no slouch, but surely he’s not faster than Critta!
