You're incredible. I guess you can tell us his velocity is up this spring vs. last spring - but you have no idea why, or if that means anything at all. For all we know, last spring he was holding back in an effort to improve his command (something he did for his first couple starts in the regular season) - or maybe he was building up strength in a different manner (pitchers build up strength and velocity as spring training goes on...very common). I'm suggesting that making conclusions based on some spring training velocity is short sighted.
Last start he went 6 innings - great...what about the ones before that? That's great he had good velocity in his first start of the year when he went 6 innings. Can he sustain that for 15-20 straight starts? Time will tell.
I'm fully believe Sanchez can improve and surely hope he does. I'm rooting for this kid as much as anyone. I'm simply concerned he hasn't been able to develop quality secondary pitches (which he's been trying to for 6-7 years now with no success). I'm encouraged by the BB% this spring - but it's unheard of to go from 5 BB/9 to <2 or whatever he's shown this spring. I think he can have some success if he can get the walks down around 3 BB/9 - but even that's a massive jump. It took Randy Johnson, one of the best pitchers of all time 6 full seasons and over 180 starts to get his BB/9 under 3.
Based on all that - I'm simply suggesting those who have his hog lodged in their throats to simply pump the brake a little and acknowledge these spring training starts vs. horrible competition may not be signs he's going to challenge for the cy young this year.