I have written before in my article on Common orthography that the acute accent symbol, in Common called 'na can pah' (literally 'stress mark'), indicating irregular stress is optional in real day-to-day writing. The can pah can appear on any of Common's six vowels. I use it consistently on this blog, since my audience is unlikely to be fluent in Common and may value the additional information about correct pronunciation. However, in most natural contexts, the accents are more likely to be omitted than used. I want to speak a bit to why that is the case.

Historical Context

The can pah goes back a long way. The original Old Common romanisation used for the Hillbillies screenshow did not use any accents, because the glyphs used to write the language in-show did not have stress accents and the romanisation was a one-to-one with the Common glyphs for the benefit of art department. The more 'phonetic' script used by the actors sometimes used ALL CAPS for stressed syllables, but this was not applied consistently.

The first appearance of the can pah was in the early period when material on learning Common began to show up for sale on the mass market and the art department romanisation became the de facto preferred Common script. The acute accent was introduced to aid learners in working with irregular stress. Irregular stress is much less common than in English, but where it occurs, it is phonemic.

In the subsequent eras, the use of the can pah was inconsistent - speakers generally assumed the can pah was 'correct', but it was often slower to write on most keyboards writers were using, so there was a wide tendency to omit it for speed.

A key factor that should be noted, as it played into later debates, was that a lot of vocabulary was being borrowed into Common, and borrowers were often borrowing it with its native stress pattern, if applicable. The can pah, when employed, aided this retention of native stress, and conversely, its omission played into the trend to regularise borrowing to have a typical Common initial stress.

Modern Usage

You would think that the massive regularisation effort of the early modern period would have settled the stylistic debate for Modern High Common. However, that is not how things worked out. This little accent mark has been a driver of ferocious debate and strife within the AXZ (na Akkatemi na Xafen Zisse, the Common Language Academy) right from that body's inception, and in the larger community of serious writers.

In that era, there were two major goals the Commonisers were working towards. One was the expansion and standardisation of the language. The other was training an army of teachers and getting millions of people to start speaking the language practically overnight. These two sides were at odds when it came to the can pah.

The pedagogical side of the AXZ badly wanted the can pah, seeing it as an invaluable tool to guide learners to proper pronunciation. However, the standardisers, led by the head of the AXZ himself, Dr. David Chang, were against it. They felt that the phonemic non-initial stress in Common was fairly regular and predictable, and that furthermore, the Commonising tendency to shift stress of loanwords to the first syllable was considered to actually be a desirable outcome. The standardisers were certainly no slouches when it came to borrowing massive amounts of new vocabulary to quickly achieve their mission of expansion of the language's technical competence, but they didn't actually respect the source languages and wanted to discourage that tendency in others.

Neither side was able to win that debate and in the end they agreed to disagree. Materials made for schools tend to use the can pah meticulously. Average people often omit the can pah for ease in writing (no doubt related to the Chang faction's interference, normal Common keyboards don't make the can pah particularly frictionless). When it comes to the most formal, official documents, you might find either style, or a mix, but the can pah-less style is more prevalent.

The opinions of influential writers on the can pah are similarly mixed, with some swearing by it and others saying the can pah is unnecessary, flow-breaking and even ugly. While the can pah spent most the previous century losing ground, I have noticed a certain fashion amongst younger writers to use it, so I don't think the debate is going away any time soon.