The phrase "one obvious exception" is correct and usable in written English
You can use it when an exception to something is immediately apparent and needs to be identified. For example, "Most people agree that it's important to eat nutritious food, but one obvious exception is people with certain dietary restrictions."
There is one obvious exception – and a debatable one.
Banks were also showing signs of recovery, with one obvious exception.
He will, with one obvious exception, have also ignored the royal presence of Tiger Woods.
Among categories that might not seem to fit the analysts' rules for online success, one obvious exception emerges: personal computers.
(One obvious exception would be any attempt to create a theocratic Supreme Court which still seems unlikely).
Cass R. Sunstein, a professor at the University of Chicago Law School, said Mr. Reagan's was "the most important presidency of the 20th century, with one obvious exception": Franklin D. Roosevelt.
His goal was to make the film that his wife would have made, he said, "with one obvious, glaring exception, and that was the director".
No one with the obvious exception of LeBron James, who on Thursday scored 19 points in the third quarter alone in a desperate, and ultimately futile, attempt to keep his team from the brink of a series defeat.
"The U.S.'s cultural belief that women are responsible for our own reproductive systems (with the one obvious, minority-view exception) and families are responsible for their own children in nearly every way leads us into some backwards policies, like the refusals to fund Planned Parenthood or Head Start in some communities.
Some question the former press secretary's loyalty and timing, but no one -- with the obvious exception of the White House and its apologists -- questions the factual basis of his claim.
All of these new features will launch on the web, iOS and Android (with the obvious exception of one-click installs, which only work with Android).
