Now that I've shocked and angered you...
Whilst I generally believe Sheldon Brown to be accurate in most of the bicycle related information he dishes out, I have to take umberance with his advice regarding bicycle sizing.
"Up until the early '80's, this was a fairly easy question to answer. You would stand over the frame of a bike, and if there was an inch or two between the top of the top tube and your tender parts, that was the right size"
Really?, maybe this is an American thing as if you could stand over a frame without leaning slightly to one side here in the UK the frame was generally thought of as being too small, granted it seems we had rather more choice when it came to frame sizing than yourself (frames would usually be sized in 1/2 or 1 inch steps).
"It is obvious why you shouldn't have a bike that is too tall to stand over with a reasonable safety margin (although even this sizing practice was not universally accepted for the first 30 or 40 years of the diamond frame.)
On the other hand, why shouldn't you ride a "too small" bike? "Because the seat and handlebars will be too low!" That was a good objection ten years ago, when tall seatposts were a rarity and quality handlebar stems were available in a variety of forward extensions but only one (short) height.
All that was before the mass production of the mountain bike. Now 250 mm and 300 mm seatposts are stock items, and a variety of excellent handlebar stems are available"
There is little need to stand over a bicycle with both feet flat on the ground, it easy to learn to lean to one side, as used to be the case(up to the 1980's, not turn of the century). This is not dangerous.
Ultra long seatposts and stems are a kludge, they aren't as strong as frame tubing, long quill stems exacerbate the fact the the plug/wedge is the only bit holding the stem to the frame and the whole thing looks dreadfully ugly.
"With the smaller frame sizes used now, the "7" shaped stem is an atavism, a stylistic holdover from an obsolete technology. An extended "7" stem is two sides of a triangle. A stem that follows the diagonal, directly from just above the headset to the handlebar clamp makes more sense geometrically. Such a stem would be as strong as a similarly made "7" stem, but substantially lighter. It would also be more crash-worthy. Modern Allen-bolt stems are certainly safer than the old style that had a protruding hex head and a sharp rear corner, but the shape is still a threat to the rider's groin in a collision.
There is a trend to use "mountain-bike type" stems on road bikes, and it really makes a lot of sense. All that the "7" stem has going for it is tradition."
If a riders groin is near enough the 7 stem that there's danger of a collision then all their weight is going to be so far forward that the rear wheel is lifting and they are destined to go over the bars, rather than collide with the stem.
Mountain style quill stems are ugly and a kludge for frames that are too small and once again are exacerbating the problem of an ill fitting stem held in solely by a plug/wedge.
"This isn't nearly as common as it used to be, since the abandonment of a slavish dedication to the level top tube, but used to be widespread."
And what was wrong with a level top tube, at least we knew where we stood regarding frame sizing. These days there is all manner of fit kits and other voodoo just to fit a bicycle. The compact frame may be slightly stiffer, but the long old seatpost and stem needed are far flexier than a properly fitting traditional frame would be.
Why buy a frame and then have to buy aftermarket components just to fit the damn thing, buy the right size frame first time round.
Lastly, by the time most people get the handlebars high enough to be comfortable for general riding, they've found the top tube is now far too short, as their reach has improved from their elbows being bent at much nearer to right angles than when the stem was further down.