I get what BBZ was trying to do. But to say speed is a CON for midfielder is just SO WRONG. I cannot think of a world class midfielder who is a speedster in the past 20 years. Some are slower, some are faster. Name a worldclass midfielder who is well known because of speed for me then.
About Arthur's pace, we will see more of him and estimate him better over time.
About pace in general for midfielders, it is a skill.
Everything is a skill and can improve your passing, shooting, defending, covering.
Passing is a skill.
First touch is a skill.
Off the ball movement is a skill.
Defending is a skill.
Pace is a skill.
Strength is a skill.
Stamina is a skill.
Ok, some skills are more important for a certain position, but at the end of a day, everything is a skill and imo it is silly to ask: why would you need a pace for a CM?
Well, a few examples, let's take Rakitic, who is quite slow:
1. if he were faster, he would have slightly more time to get an advantage after dribbles or getting a loose ball, to think what to do and make a perfect pass
2. he would win more loose balls in the middle of a pitch (with better acceleration and pace)
3. from time to time he would get into an open space and receive someone's through ball
4. when dribbling, he wouldn't lose the ball so easily as today
5. in defending, against speedy opponents or wingers, he would be even better to close down or make a tackle
6. when he gets the ball around the box and makes 1-2 steps before shooting (to get into a better position), with more pace/acceleration, he would have a few miliseconds more to try a perfect longrange shot without being closed down, pushed or tackled from a defender
So, more pace will give you a few miliseconds extra in majority of attacking and defensive events during the match... UNLESS if we play against a parked bus consisted of 10 defenders when our players are just passing the ball from left to right, then you don't need (too much) pace in that scenario.
The same is about stamina.
The more you have it, the longer you will be able to play at 100% during 90 minutes.
The less you have it, you will start to lose a few miliseconds and inches in every pass, every tackle, every run for a lose ball, every jump for a header, every shot from the edge of a box.
You won't be at 100% anymore, but 90%, 80% as the match goes by.
Also, I feel that majority will reply: Xavi was slow and look how good he was.
Well, he wasn't good BECAUSE of his poor pace, but INSPITE of it.
Imagine if Xavi was faster. Whatever he was doing, he would get an extra 10-20% to it.
Plus, he was the best passer of all time, so we shouldn't even compared anyone with him.
He was sooo good that he didn't need pace.
But for other players, who are humans, pace, stamina, strength, all skills will improve your overal abilities.
Also, during the last 2 years, majority of us made a lot of jokes about our turtle midfield when we had Iniesta-Rakitic-Busi.
A lot of guys were writing in the last few Months how we need a faster and more mobile CMs and how RM's midfielders are faster and more mobile than ours (at least Isco, Modric and Casemiro).
In that sense, for now, Arthur isn't improvement in terms of our slow midfield.
We could debate whether pace could improve a midfielder only by 1% or by 50%.
But again, pace is a skill.
Tonight is a 2nd match.
We will see more about all new players (Arthur, Malcom, Lenglet and Bteam players).