If you check the previous posts, much of the discussion centers around fit/stem angle and length. I wonder if this isn't one of the aspects of modern bikes which is retrogressive, rather than progressive. If you determine the torso/arm length measurements of the proposed rider, and then were to go out and find a '80's era lugged steel used bike that has a total reach (top bar length + stem length), that would work, then he could play with stem height all he wants, and may wish to lower it as he sees fit as his flexibility increases; or conversly leave the stem high if there is a lower back problem, and a lack of said flexibiltiy. My point is the '80's era bikes did not have the restriction of fixed stem heights, did not require stacking plastic bits to achieve a desired height, and if needed-can be replaced with a stem with a longer or shorter reach for around $15 on e-bay. This novice rider does not need to save the weight penalty, and the theoretical stiffness issue is debatable.

Find a vintage Bianchi, or other with accomodatation and clearance for fenders and possibly a rear rack, and send him off to an intenet site to determine "total reach"-ie Wrenchscience, and then research saddles with the aime being a continuous 2-hour ride with no pain; and he would be alot further ahead. If he wants to try the bar 2" lower than the saddle, an allen key and 10 seconds can give him this correction.

Tell him that the experience should allow him to mentally drift, and that the ultimate aime is to "wake up" on route and find that you have been in the drops for the last 45 minutes by subconscious choice.

He may find that he wants to get something new after this experience. The money out may be $250, with a resale around the same price. Then he knows what to look for, and a further outlay of $800 or so, may be justifiable for him for the 5 pound saving, and some other secondary benefits. Leave all that debate about stem height and length vis a vis saddle on the table.