Bevan Brittan would perhaps have been well advised to follow Mark Twain's famous game plan for success – put all your eggs in one basket and then watch that basket.

Instead, the firm has spent much of the last four years since its demerger from Bevan Ashford agonising over whether to spread out further beyond its undoubted public sector/health prowess.

As one former partner observed: "Nobody ever quite wanted to acknowledge Bevan Brittan's strength and just do public sector work. In a way, it was always paying lip-service to building a private practice." But after the firm last week announced that up to 40 jobs could go in a redundancy programme across its offices in London, Birmingham and Bristol, it appears that the debate has now been painfully resolved. The expectation is that the firm will in the future be rigorously focused on its core market.

Yet it does seem ironic that in this market, in which a firm like Bevan Brittan would appear to have been well-hedged, that it would become one of the first major law firms to make job cuts.

The apparent reason behind the cuts is the firm's faltering attempts to build a general commercial practice. One partner at a rival firm comments: "In a boom time any firm can do OK, but in a bad market the firm did not have the strength of practice, lawyers or repertoire to keep it going – their heart was not in corporate and banking."

There are also claims that the firm was undisciplined in some of its expansion, especially in the back office. This could be one reason why such a large number of support staff/secretarial jobs went as part of the cuts – 34 out of the 40, a considerable cut for a firm of its size.

In the midst of a declining market, a number of departures this year, such as those of intellectual property duo Georgie Collins and Harry Karaolou to LG and pensions head Gary Delderfield to Eversheds, have been cited as evidence that the wider commercial push was failing to gain momentum.

The firm is obviously very good at public sector work and has built a well-regarded, market-leading practice advising bodies such as the NHS Litigation Authority, a number of NHS trusts and the Welsh Assembly. The firm's new strategy seems to be adopting a realistic approach and bedding down to its core business and clientele. One thing that may turn out to be a saving grace is the neat property deal involving the sale and leaseback of the firm's Bristol office in 2007, which helped to substantially raise the firm's partner profits.

The firm claims it is not ashamed of its public sector focus, although cynics might question how that has chimed with its post-demerger strategy. But the challenge now will not so much be whether it is sustainable for a large firm to focus on the public sector – it more about whether it is sustainable for this firm to focus on the public sector.

There will be a number of rivals, particularly in the clubby Bristol market, that will be ready to pounce during this moment of vulnerability and recruit senior lawyers from Bevan Brittan's core teams. The challenge will now be to get some momentum around its relaunch. No doubt all eyes will be on the proverbial basket this time, but the worry for Bevan Brittan is that the egg-based cliche on rivals' minds will involve omelette and eggs of the broken variety.