In a recent blog about five delusions commonly shared by law firms, I was greeted by the unusual experience of readers agreeing with the points I made… with one exception. This was my claim that law firms shouldn't kid themselves that clients ignore directories – hence this follow-up.

Well, the bad news for those hoping for me to put the boot into the large directories like Chambers and Legal 500 is that I stand by it. I certainly accept that clients routinely downplay the extent to which they use them. Of course they do – you already have panel reviews run by bank procurement teams in which they are embedding directories into the pitch process.

Let's be realistic. For in-house legal teams, a directory is a potential threat because it demystifies the procurement process – a major part of their job. Many counter that clients have a hugely sophisticated view of the market and don't need directories. Rubbish. If you're a lawyer in a company, your job is (rightly) focused on achieving the ends of your employer and furthering your career. You will have not the time, inclination nor need to spend your days scanning the horizon to buff up your knowledge of external counsel. (Much as law firms like to think clients spend a lot of time thinking about them, they really don't).

This means, with the exception of a few industry sectors that operate very large panels or that build very specialist in-house legal teams, clients' knowledge of law firms other than those they instruct is sketchy. It's obvious to see how this dynamic creates a role for directories in a very fragmented market.

What about the claim that no client ever instructed a law firm for a large job thanks to a directory? It's facile. Of course, you're not going to get a seven-figure gig solely on the basis of a directory entry. But that's a completely unrealistic benchmark that no reference tool in the world would pass. What they are often is part of the process, either in sophisticated markets as part of the box-ticking pitch element or for more direct introductions in less developed regions or niche areas. What more could you expect? (There is also no doubt that directory rankings are widely used in the recruitment process by firms looking to vet laterals and junior candidates checking their target employer).

Of course, it's not just about whether they are used – many criticise directories for a lack of rigour and argue law firms game the research process. There is something to this, but my impression is that – while a few howlers slip through – they are overall a reasonable reflection of perceived reputation. In this regard, law firms shoot the messenger because that perception is what they don't want to be reminded of, and in some cases will lag reality. But it's not a failure on the part of directories. Gaming the process? Sometimes, probably. But since the backbone of Chambers and Legal 500 are interviews rather than law firm submissions, I doubt it's a major factor and anomalies will smooth out.

The more honest BD staff will also admit that the perennial complaint about the lengthy submission process is a tad hypocritical. The major directories ask for fairly brief fact sheets – it's law firms themselves that, brimming with partner egos and the inability to submit anything without 57 sign-offs, that put much of the pain into the process.

If this all sounds like a love letter to the directories, they obviously also have their issues. They're on a sticky wicket on the greenness of their researchers and the high turnover of staff. Over the years, I've hired three reporters for Legal Week who had worked at a major directory. All were bright and reasonably able. But we had to do as much work teaching them about the industry as we did the reporters that joined with no legal background. It wasn't a great advert for the directory's industry nous. (Set again that, a friend of mine with superb industry knowledge did his first job on a directory). But they should certainly make more efforts to retain their researchers for longer.

Rigour of the process? It can be a bit rough and ready, especially as they have spread themselves so thinly with proliferating international editions. And it's hard to refute the claim that the process has inherent upward bias that means more firms get ranked every year. But, by many accounts, Chambers in particular has put in place a well-structured process in recent years and one that also gives particular weight to client interviews rather than private practice.

It would, however, be fair to say that the major directories haven't always been very responsive to their law firm clients. Indeed the relationship has often bordered on the dysfunctional, a factor not helped by law firms usually complaining in private rather than putting their foot down or robustly engaging with the directories. Both sides could do a lot better on this front. And, yes, a business model built around classified law firm profiles, which no one has read since the dawn of the interweb, is now somewhat curious.

But overall, they do a decent job, bringing a little more transparency to a fragmented market. Perhaps the biggest evidence of their success is actually the level of griping they generate – no-one ever moans about the irrelevant, they just ignore it.