So what are we to make of the latest Michelin Guide, which awarded two new stars to Scotland while taking two away?

And fixed a shiny new bib gourmand to two funky, mid-priced Glasgow restaurants - one of which opened only five months ago? Edinburgh also gained a new bib, bringing the two rival cities neck-and-neck with three each in this category, which is defined as "good food at moderate price". It was good news for Glasgow, which is desperately in need of recognition for its recent grassroots food revival.

On the other hand, it still languishes without a star, while Edinburgh retains an impressive, though also unchanged tally of five stars. Overall, Scotland has been stuck with 15 single-star restaurants and one two-star restaurant for years. I find this stasis frustrating.

The real fallout happened outwith the Central Belt, and many observers were perplexed by it. The Three Chimneys on Skye was one of the recipients of a new star (awarded for "very good cooking in its category"). Chef director Michael Smith has been at the helm there for no fewer than eight years. Head chef Ross Stovold at Isle of Eriska, the other worthy recipient, has been cooking there for 14 months. So there's a contradiction for a start. It used to be that proving consistency of quality in food and service over a period of time was necessary before gaining a star, but that theory was thrown out of the window in 2007 when The Kitchin got its star within six months of opening. Why did it take the Michelin inspectors so long to cotton on to The Three Chimneys? I wonder if it's down to a change of editor - and a change of criteria.

The losers for 2015 are the luxury Inverlochy Castle Hotel near Fort William, which has held a Michelin star continuously since 1998, and by current head chef Philip Carnegie for the last five years; and Glenapp Castle at Ballantrae, Ayrshire. Its new young head chef Tyron Ellul is presumably too recent an appointment and didn't have enough time to prove he can hold the existing star (though I notice he was recently listed as a Chef to Watch in the Good Food Guide 2015). When I asked the Michelin Guide editor Rebecca Burr why Inverlochy had lost its star she declined to give details, saying only that maintaining standards was paramount and that deleting someone's star was "one of the most difficult apects of our job".

Restaurants with stars run by Andrew Fairlie, Martin Wishart and Geoffrey Smeddle have all developed their cooking over the last year, with no change. It does raise the question of who the inspectors are advised by. I am told there are several ways Michelin decides which restaurants and hotels to visit: reader recommendation (email, phone, letter, questionnaire in the Guide and now Twitter), requests from the businesses, and intelligence gained by the inspectors.

That's the thing about the Michelin Guide. Like royalty, it reserves the right to absolute discretion. Some observers claim there are only around 12 inspectors in the UK - hardly enough to cover all bases, I'd have thought - but the Guide itself won't confirm how many work on each patch, because "they can cross country/continent boundaries to make sure standards are consistent around the world". They try not to make frequent repeat visits so they're not recognised and often dine in pairs, the better to flummox front-of-house staff.

One inspector did reveal that everyone thinks getting stars is about the surroundings, table linen, service and so on, but it's actually only about the food. That echoes almost exactly what Burr said when I asked about the mushrooming of bib gourmands (up 26 to a record total of 115 across the UK) compared to stars (14 new ones, nine deletions). She said that while stars are still most important, there has been a new focus this year on competitively priced, less structured and more flexible dining. Stars were awarded to pubs, "hipster hangouts" and counter restaurants as well as classic dining rooms. It's tempting to infer that Scottish castles are now seen as very last year, while the relaxed vibe of The Three Chimneys and Isle of Eriska is more "happening".

In urban Scotland this new trend is most clearly reflected in Glasgow. Given the success of The Gannet, Ox And Finch and Stravaigin, I'd say they're giving Glasgow what it, and the Guide, wants. The logic follows that it should stop fretting about having no Michelin stars and instead celebrate its budding popular revival.

All well and good for those who get the recognition. But it doesn't explain why restaurants such as Ondine, Timberyard, Cafe St Honore and Gardener's Cottage in Edinburgh, Brian Maule, Gamba and Cail Bruich in Glasgow - to name a few - keep being missed out of the Guide. Perhaps what they do simply doesn't fit into any fixed category. Another question is whether bibs should be expected to develop into stars. Not every restaurant wants one, even if it boosts income, because the pressure to maintain it is so stressful. Neither would they want to change what they do so brilliantly - cook great food that pulls in the punters.