I have found that “tall” generally has no finite attitude to it when looking at physiques. The defining point(s) that I witnessed were the strength and coordination qualities of a “tall” pitcher.
Some “tall” pitchers are very brittle in their movement, while others are very strong and aggressive. “Tall” pitchers must bring a certain weight-to-mass ratio, that’s a must for athletic competition. Weight is usually self defining, but mass is a tricky thing to judge, especially in proportions to the man’s build. Guys over 6’ 3" are a tricky lot to hang one’s hat on, very tricky. In fact, I think the “tall” pitcher is the most challenging of all physiques to judge and evaluate - especially going into the prospects category.
“Tall” in my estimates would be anyone over 6’ 4".
With respect to my statement about weight and mass, I’d look at a pitcher 6’4" this way.
If he was about 185 lbs., I’d be seeing probably a brittle physical (mass) performance more than likely, with an overall life expectancy of about three innings of quality work, at best. On the other hand, a 6’4" pitcher weighing in at 225 would have a better chance of sustaining himself, everything being equal, with a sturdy physical (mass) performance.
What enters the mix next is the pitch inventory that the man brings to the table. Tall pitchers who deal nothing but gas, had better have a physique and a frame to deal gas on a regular basis, without being eligible for a rehab session every three or four months. A good solid pitch inventory that mixes gas with a solid change-up, is golden.
I’ve never been one to bank on what’s in fashion at the time. Tall guys that have a weight to mass ratio that’s strong and durable are a definite dime in the bank, no doubt about it. The trick is to balance weight and mass that works, based on age and projected longevity.