I think, Yasir can be a good ODI spinner, if he is used properly. In Test matches, he is used as wicket taker & he bowls well when he is allowed to attack. I can safely say that at Manchester, he bowled the fastest, once England had a big partnership, Misbah asked him to "tighten screw".
In ODI, he should be even more effective considering the quality of spin play these days. But, he is used as a container, which will never make him lethal. These days, every team analyze the game & they'll find 2/3 target areas against him - without taking much risk, they'll milk around for 4/5 singles & in between take calculated risks.
Shane Warne played most of his ODI in 90s & many of those at home, when the AUS grounds were 90mts+ boundary - still that guy has an economy of 4.3, which is HIGH for that decade. That's because, not for a single ball, Border or Tubby or Steve used him to contain runs. He was a genuine match winner, who bowled in ODI's almost similarly like Test - attacking length, line, speed, flight & catching fielders. I can recall the IND-AUS WC '96 match at Mumbai, when India's asking was around 5 & in 42nd (or 44th) over Talylor gave him a slip & 6 men in ring - eventually he got the vital wicket (Mangrekar ?) caught at slip.
Azhar (PAK) is using Yasir exactly like Afridi, but both are totally different spinners. By trait, both are leggi, but it's like using Kumble & Warne same way. Afridi was faster, hardly any turn, but quite accurate - so he was more of a pressure bowler, a squeezer, who'll increase the pressure by blocking boundaries & increasing dot ball. Yasir simply can't do that - because his weapon is his turn, variation, loop & flight.
Yasir should be used as a Test match bowler - to get wickets in middle overs -
1. give him longer spells, preferably 5+5, in not 10 at a stress (leggis need to settle down)
2. don't bring him with newish ball (Badree is not a leggi, he is slider), may be bring him after 23 over & give him 10 overs at one go
3. Use him to get wickets - when only 4 fielders were required, still Aussie Captains used 6, sometimes 7 inside circle to Warne; so did Wasim with Saq & Mush. Now, there are 5 already, 1 more doesn't hurt much - give him 6-3 field with a slip & 3 men patrolling covers; keep mid-on or mid wicket in & encourage batsmen to flick/loft him against spin.
4. encourage him to get wickets, 3/72 is acceptable in a 300 per course, if he is taking those 3 in between over No. 20 to 40.
At present operating mode, he'll become confused, frustrated & might lose confidence, which is the key to leg spin. He is such a great asset in ODI - brilliant fielder, can bat, can hit & a master leggi. He should be twice the bowler Tahir is.
Leg spinners need attacking Captains - Imran always picked Qadir over Tauseef or Qasim, if he was to pick 1 spinner for ODI; Wasim as well - for 3/4 years (before Saq), Mushi was his 1st choice spinner. Arjuna carried someone as ordinary as Chanda, for many years - whereas, after 1st ODI, I knew that Mathews will drop Sandakan, because he leaks runs. But, his counterpart (Aussie Captains) are using Zampa to get middle-orders out.
Sorry story for Yasir - he'll never prosper in ODI if Misbah, Azhar's Captaincy philosophy prevails.
... yasir lost his ODI spot due to pathetic captaincy..
As he said in the press conference, they want him to play in ODIs. Also of Irfan in LOIs. 
