In March, three months into her leadership, Johann Lamont laid down an uncompromising message to her Labour colleagues.

"The next 12 months will be a period of renewal for our party in terms of structures, organisation and policy," she declared.

Responding to her party's shattering Holyrood election defeat, Lamont promised to rejuvenate an internal structure that served only to "stifle" talent. At first glance, the last fortnight shows that Lamont should be taken at her word.

Rami Okasha, a party spin doctor believed to be closer to Scottish MPs than MSPs, was suspended over alleged "insubordination". Days later, Scottish Labour general secretary Colin Smyth announced he was standing down from his post.

The moves seemed evidence that Holyrood Labour had squared up to the party's Glasgow headquarters in John Smith House, long viewed with suspicion by Labour MSPs as being Westminster-oriented.

However, Labour figures talking off the record say it would be unfair to pin the "problem" on two individuals who served their party.

The senior insiders believe the central issue – the failure of Scottish Labour's HQ to respond to the party's devolution agenda – goes back 20 years.

As one source put it: "Labour created the Parliament, but power was never devolved in a similar way to the Scottish party."

This was evident as far back as 1992 when Jack McConnell was asked to attend an interview for the Scottish general secretary's post in a Preston hotel. Alex Rowley left the same job in 1999 amid claims he had been axed by the UK party.

Despite Scottish Labour helping to deliver the most radical constitutional change in more than 100 years, the party's HQ and staffing were largely funded by the UK organisation.

There was also no "Scottish" leader: in a devolved context, there was only the leader of the Labour group at Holyrood.

For the first decade of devolution, party sources say John Smith House prioritised Westminster over the Scottish Parliament.

"HQ was a wholly-owned subsidiary of the MPs," said one former MSP. "They did the bidding of Westminster, not Holyrood".

A senior Labour trades unionist said the relationship between Holyrood Labour and John Smith House had "broken down" by the time of the 2007 Holyrood election.

During this disastrous campaign, three tribes occupied different parts of the same open-plan office: First Minister McConnell and his coterie of advisers; strategist John McTernan, who was the Downing Street link; and MP Douglas Alexander, a proxy for Gordon Brown.

As one insider joked: "I think the three camps walked in different parts of the same stairwell."

In September 2007, the election of Wendy Alexander promised the far-reaching internal change many felt was required. She and campaign manager Tom McCabe were determined to turn Scottish Labour into a federal party, as well as overhauling candidate selection and fundraising strategies.

As McCabe said at the time: "It's clear we need more autonomy, more responsibility over our policies."

This reformist zeal alarmed key party figures. After Alexander's first conference speech in Aviemore in 2008, a story broke that she had been taking advice from Philip Chalmers, a former special adviser who had resigned years earlier after being caught with a sex worker in his car.

A source close to Alexander said: "I've got no doubt John Smith House had a hand in leaking that information."

Her reign also coincided with the appointment of a new general secretary, the low-key Smyth, to replace the outgoing Lesley Quinn.

Again, his appointment process raised eyebrows. Although Smyth would be expected to implement the Alexander revolution, the interview panel for the post was dominated by UK party figures.

One Scottish Labour insider said Smyth, an ally of Quinn, was a "placeman", adding: "Colin was always the least likely to be the candidate with ideas."

When Alexander resigned over a donations scandal, her reform agenda also died.

Her successor, Iain Gray, showed little interest in internal reform or changing the culture and practices of John Smith House.

"Iain Gray was there to build bridges," said one insider.

Although the Scottish party HQ masterminded a successful General Election campaign in 2010, this proved to be a false dawn.

The 2011 Holyrood election provided a unique set of challenges for Labour, but Gray, his deputy Lamont and Smyth opted for a rerun of the anti-Tory message that had worked 12 months before. It failed hopelessly.

Gray's lack of interest in reforming John Smith House manifested itself in other ways. While the SNP was adept at using social media to win votes, Smyth and his colleagues were sceptical.

It is believed the party HQ was wary after Westminster election candidate Stuart MacLennan described old people as "coffin dodgers" on Twitter.

Gray's team was also irritated by the attention John Smith House gave to the then Glasgow City Council leader Steven Purcell. "He was their golden boy," one source said.

The 2011 election handed the SNP a historic majority and was followed by a full-scale review of Scottish Labour. The inquiry led to MSPs, MPs and former parliamentarians issuing damning judgments on the internal machine.

The review backed reforms considered to be long overdue, including the creation of a new Scottish leader who would call the shots on behalf of the whole party.

Some party sources believe this upheaval explains last week's events involving Okasha and Smyth. According to this theory, both failed to reconcile themselves to the new structure that Lamont finds herself leading. That meant they had to go.

However, other senior figures believe Okasha and Smyth should not be made scapegoats. One suggested Okasha's problem stemmed from a turf war with Lamont's new spin doctor, Paul Sinclair.

"Rami was very able. He was effectively doing three jobs before the Holyrood election," he said.

Another source said Smyth has ambitions of becoming a Labour candidate for Westminster.

Senior party figures also told the Sunday Herald that last week's departures were spun heavily to make Lamont look good.

The media consensus is that the Glasgow Pollok MSP has had a solid start as leader, but the reality is more complex.

Difficult policy decisions have still to be made, while the much-vaunted "Devolution Commission" she announced in March has yet to meet – or even agree a remit.

However, as one MSP pointed out, there was only one winner last week: "The power has shifted to Johann. Her new team will be answerable to her and the Scottish Labour party."

Lamont emerged from the last week with her position strengthened, but even her strongest allies would concede the road to becoming First Minister will be long and arduous.