The most common and most likely answer to this crossword clue is the 3 plus 6 letter word OLD SCHOOL
I've seen this crossword clue in Financial Times
O
L
D
S
C
H
O
O
L
More clues leading to the result OLD SCHOOL
- Conservative keeps calm, with hearts sinking
- Group of Conservative thinkers from Winchester?
- Requiring courage to dispense with British coach for adhering to traditional methods
- Conservativeās alma mater?
- Favouring traditional methods of former coach
- Conservative beginning to offend Liberal Democrat on train
- Traditional tie may follow this
- Yet this institution can give modern education
- Conventional way of thinking from what brings alumni together
Buddy explains!

The straight part
We know that "adhering to traditional methods" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case adhering to traditional methods = old school.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does OLD SCHOOL mean?
OLD SCHOOL noun- A style, way of thinking, or method for accomplishing a task that was employed in a former era, remembered either for its inferiority to the current method, or for its time-honored superiority over the new way.
- Characteristic of a style, outlook, or method employed in a former era, remembered either as inferior to the current style, or alternately, remembered nostalgically as superior or preferable to the new style, the older denoting something that would be considered out of date or out of fashion to some, but as such, is considered by others as cool and hip.