Saw this on the other BCB and could not find it here, so I thought I might share.  Very informative (though I am not sure how reliable as I have yet to see these projections applied and the subsequent results).

Of course, the most fascinating part echos thoughts posted here regarding Saturday's game.

Marmol & Science

Quotes:

The Gist-

Marmol began the year on fire and had a terrific April and May thanks to incredible speed and movement on his fastball and his electric slider. As the calendar turned to June, Marmol's stuff began to slip and he paid the price. While his slider appears to have regained form, his fastball still isn't back. While a much straighter 95 mph fastball still is an effective pitch, it isn't anything like what he was throwing previously.

I don't expect Marmol to regain the elite fastball the rest of the year because he didn't seem to regain it after a light June and it isn't likely he will have more rest than that from here on out. He is going to have to learn to get big league hitters out with just a very good fastball. Obviously that can be done, but it will be a transition for him. Expect his strikeout rate to drop back down closer to 10 per nine innings than the 13 he has posted.

The walk rate will be the big key. In the past month Marmol has put on nearly a batter an inning via walks and hit-by-pitches. While I expect that to go down, I do expect him to continue to walk a batter every other inning or more. That is playing with fire and with his straighter fastball he is more than likely going to continue to get burned with the long ball from time to time. This combination of walks and more home runs will likely cause Marmol to be very erractic, throwing up a few zeroes, then exploding and give up three or four runs, then going back to throwing goose eggs. June will likely be a typical month where he looks great in the middle of the month then struggles at the end of it.

The Warning -

The Cubs have to be careful not to overuse Marmol. It seems pretty clear that when he is worked hard his stuff suffers, so Piniella needs to find that sweet spot where Marmol is still effective but not overused, or else we might see even more degradation in his pitches.

The Saturday Bit Lou Shoulda Read Friday -

So if you have a shaky reliever like Marmol, the time to use him is in high leverage situations when putting up a zero makes a huge difference but the difference between giving up one and say three runs is small. The worst time to use him would be a situation where you were up three in the bottom of the seventh. In situations like that he is more likely than a steady reliever like Bob Howry or say Neil Cotts, depending if you want a right- or left-handed pitcher. Those guys aren't as likely to throw a perfect inning but they are also less likely to blow up and give up the entire lead.

Personally, I had read this situation as a Head issue where Marmol seems to fall apart.  But, that was because the Slider looked pretty decent.  I had not paid much mind to the Fastball (other than velocity).  Would more informed readers care to weigh in?