The issue in overoaked wines is not excess, it's artlessness.
Jim Concannon used to say that oak should work in wine like garlic in cuisine -- you use it to accentuate and lift the wine's native flavors. On the other hand, there do exist "lovers of the stinking rose," and sometimes to appeal to these freaks (as at the Gilroy Garlic Festival) garlic becomes the whole theme of a dish. It's fun for a while. So with oak, and many a novice has been temporarily taken in, later to scorn its excessive use.
I remember the first Bordeaux I fell in love with to the point of buying two cases: the 1970 Clerc-Milon. By the 24th bottle, I realized my error -- the wine was nothing but oak. I joined the ranks of the no-cheap-tricks-please purists, where I remain to this day. Only now as a winemaker, I have learned to use oak to fill in, to support, to enhance, to cover, to frame. Thierry Lemaire, my OenoDev guru, taught me that oak should be like fine cosmetics -- done right, you can't tell she's using any.
But discussion from wine critics and buffs centers around quantity: what percentage new oak, how long in wood, and so forth. This is focusing on the wrong thing. How apparent the oak aromas are has little to do with how much oak is utilized! Tiny amounts of bad wood in a poorly structured wine will be far more obnoxious than much larger exposure handled with skill.
What determines how well integrated these flavors are is the quality of the wood and the quality of the wine's structure. Wood quality is a function of forest pedigree and skill of the forester, duration and care during drying and curing, toasting skill, and matching up of wood and wine. The wine's structure derives from the grape's native base of color and tannin, its degree of maturity at harvest, the effectiveness with which these elements are extracted during fermentation, and the skilled hand which directs the élevage process in the cellar.
Great red wine speaks with a single voice. Just as the elements of a well made sauce are not easily distinguished, so the properly refined tannin structure can hold together complex aromas as a unified aromatic whole. Only then can the wine be soulful, as in that moment when a hundred instruments of a symphony play in temporal and emotional synchrony and that big single voice it hits us viscerally in the chest and tears flow.
Some of the tools the skilled artesan can employ to achieve aromatic integration are -- surprise! -- oak components. For example, the right kind of well-cured but untoasted oak chip in the fermenter can greatly enhance the extraction of color required for fine structure. Oak -- the right oak -- can also contribute phenolic monomers to young wine which are useful in building structure and preserving fruit aromas. Sweet wood can balance heavy tannin from press wine, permitting deeper structure to be built and refined.
It's easy to get a job making wine without any of these skills. There are plenty of pricey bottles out there made by small producers who haven't distinguished quality from quantity. These days it's a crap shoot. If you're a gatekeeper or passionate consumer, you can help by getting your nose out of the tech sheets and into the glass.