Here we go again. In 2010, South Africa was convulsed by a wave of industrial unrest as pay bargaining talks lumbered into action and three years later, hey presto, the same actors seem to be going through the same painful process once more.

The ante's been upped considerably this time though, as a convergence of industrial unrest is laced with aggression that threatens to cause a domino effect of economic woes.

The country saw violence on a massive scale last year in the mining sector, where 34 protesters were shot dead, while this week alone apparently, ten more workers in the sector were hit by rubber bullets.

A general air of labour disquiet is spreading, with dire reports of workers making veiled threats to power companies the lights will be turned off unless 20% wage demands are met, while a falling rand adds to the general sense of unease that sees vague hints action will be taken 'on the streets.'

All this set against the depths of the South African winter and into the maelstrom steps the auto sector.

The car business certainly hasn't witnessed the levels of violence seen in the mining industry, but the temperature is rising as wage negotiations start their tortuous process of deliberation in smoky Johannesburg and Pretoria hotels.

Three years ago pretty much the same industrial unrest bubbled to the surface as pay talks were in full swing, with some 70,000 striking for example in the automotive component and retail sectors.

And just this week, either 1,200 or 6,000 workers at Mercedes-Benz, the automaker insists the former, the National Union of Metalworkers of South Africa (NUMSA), says the latter, went on strike.

That infamous 20% pay request, some long-held industrial grievance? Not quite. The Mercedes-Benz factory was hit by a walkout concerning: overalls.

Overalls. In a dispute that appears so obvious to resolve it seems painfully simple, an argument at the German manufacturer's East London factory rapidly spiralled from workers objecting to being asked remove their overalls when going outside before returning, to all-out stoppage.

"We believe [someone] from Germany wanted to change working conditions," NUMSA president, Cedric Gina, told me from South Africa. "That is what we are not going to accept."

"Our workers said they have worked there for more than 20 years and it has never been like that," said Gina. "The workers got wild because the manager wanted to discipline them - the whole plant said if you want to discipline them you might as well discipline all of us."

Mercedes-Benz politely replied there had indeed been "a change to procedure," but maintained the paint shop is "a very sensitive environment."

Could it be on a matter on almost monumental common sense to everyone else, it was NUMSA that was operating "in a sensitive environment" and using the eminently sensible proposal by the German automaker, to whip up indignant outrage for almost no reason at all?

It's the proverbial straw that broke the camel's back surely. NUMSA may have been itching for a trigger to spark a huge protest and they found one in the trivial matter of overalls, but why?

A clue maybe is to be found in trying to understand the lot of the South African blue collar employee. Starry promises of the Rainbow Nation have very much given way to the reality of putting bread on the table, but even those lucky enough to be in work, don't exactly have it easy.

The NUMSA president told me he was putting forward a claim for 22% for all 120,000 of his metalworker members and he must have heard the surprise in my voice when he mentioned the figure.

"The inequality in our country is so huge - for a person in the UK where maybe the inequality is not so high - you think that is outrageous but it is not," he said.

"Our country has a particular history that makes us make those demands."

Gina went on to paint a small picture of what life was like for an ordinary South African worker - even one fortunate enough to have a job in a country believed to have 25% or more than 4m out of work.

Those in employment, said the president, have to look after others on their wages, extra family members.

Added to that is the thorny issue of transportation. It's a long time since I've been to South Africa, but one of my abiding memories is how many people simply walk everywhere, long distances at that, perching precariously on the back of pick-up trucks and lorries or cramming into unofficial mini-buses.

"Most of our members live far away from [their] workplace," says Gina. "They spend a lot of money transporting themselves. There is still apartheid in terms of how things happen, where workers wake at 03:00 to prepare to start a shift at 7am."

NUMSA has a political view of course - Gina openly quotes Vietnamese communist leader, Le Duan, as saying: "A revolution is a coup d' etat; it is not the outcome of plots. It is the work of the masses."

So there's no real ambiguity there and it would be fascinating to be a fly on the wall at the forthcoming talks between the union and the Automobile Manufacturers Employers Association (AMEO), which naturally, takes a more cautious view.

"Yes, we are optimistic," AMEO chairman, Thapelo Molapo, told me from Pretoria.

"The beginning of any negotiation is always full of expectation and drama - we have done this many times and I am not too worried.

"The riots we have seen in the mining sector - I am optimistic we will do much better. What we have seen in the mining unprecedented and tragic and is not how we must handle labour relations."

A relatively small skirmish concerning paint overalls may seem trivial. But it may be symptomatic of a much wider malaise.

NUMSA and AMEO will have their work cut out next week to not only address the headline issue of wages, but also the deeper societal challenges in a country still adapting to the unfettered market.

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