winter help?..

Here you go, I've read it and seen it in use. If you aply yourself to it you'll improve in most areas.
Its also a book you can use year round. I am biased, I am an administrator on his website, but I got there from looking for top flight information and a great forum for learning and sharing the art.
http://www.pitchingworkouts.com/

What about that claim for 5+ MPH in a few short weeks?

Does it hold any water?

I would suggest that depending on how one applies themselves, where they are in their own personal development (I doubt the Rocket would experience such a jump), yes you could improve velocity by a factor of that much using Tuff Cuff. I would say that a reasonable cross-section of under-classmen would have very noticable velocity improvement in that time frame.
It is a superior quality conditioning guide that is pitching specific and designed as a tracking log and isn't simply an exercise picture book, it has routine suggestions that are season specific..My sons High School coach got a copy from me..he put it into use the very next day and uses it to this day (My son has graduated).

Would someone throwing 88-92 experience a jump in velocity, by your estimation?

My brother and I are both in that range and were thinking about springing for it, especially if that claim were to be valid, as any extra MPH would be amazing, even just a couple MPH.

Well that is a toughie, as you know at that range you are not dealing with multiple mphs as you become more efficient. I'd say it will help allow your body to withstand the additional mph's. I'd say that some of the stuff could help you get the efficiencies to allow you to incrementally increase.
Sitting at that range is great and congrats to the both of you.
I think for the dollar and the impact, you could find it worth while certainly, I mean for the money it's basically the cost of 1 or 2 pitching lessons with a good instructor. Obviously you are a mature couple of pitchers who are looking to get to the next level, the book isn't marketing hype with a word of wisdom dropped here and there, it's cover to cover, very applicable exercises and drill work and charting. I think the charting is really key and excellent. So there ya go, not so clear cut but I hope it gives you a little better understanding of what it's all about.

Sorry this is late but you might want to check out this place Highlander Academy if you are in the Bronx area.

Jason:

Go to the strength and conditioning Forum and look through some of the threads there - search around. Jon Doyle's unbreakable abs is a good place to start as a foundation. Jon will put a program together for you but it will cost you some $$.
You can build up your own program by talking to Jon and other trainers, particularly sprint trainers or others who have put together baseball specific workouts.

I am a fan of kettlebells and since you are in NY Kettlebell concepts may be near you and they have some excellent stuff.

You can get bands from Jaeger sports and you can do them daily as well increasing the "throwing motion" part up to 50 times per day to help not being able to throw as much.

I have not read the TuffCuff book but have heard good things about it.

Ron Wolforth's stuff is exellent also. Generally throwing specific.

If you know anyone in pro ball they usually give their pitchers a winter work out strength and conditioning book and you can get some good information from this material if you know anyone.

As far as lifting goes, focus on legs, compound olympic style lifts. Jon has some good CD's on this if you don't know the technique, or find a trainer local to you who does.

As far as timing you are late to be getting started for a winter program, but better late than never.

As far as throwing in 30 deg weather I will have to defer to others on this. In general if you get your body temperature up and can maintain it you should be safe. There must be some lightweight clothing around that you could wear that would allow you to maintain your core warmth and throw in cold weather.

Good luck!