It is an especially interesting read in the way that it shows radically different traditions than what I read in English heraldric authorities likes Boutell and Fox-Davies.
The first and foremost point is that that Scotland is one of the few places where there is an heraldic tribunal. And it shows. There is very little 'free for all', the Lyon Court demands matriculations, and its rulings have all the weight you'd expect form a court.
Innes of Learney has a very high opinion of his art, considering it having been perfected in Scotland. And there are plenty of jabs at England's different practices to tell that there are plenty of sore spots in the relationship between English and Scottish heralds.
The big take away is that Scots heraldry is a natural expression of the ancient Scottish celtic clan system. And since almost everybody is related in some way or another to a clan chief, that means that pretty much everyone is eligible to bear arms. And because the differencing scheme used yields a strong resemblance in the arms of all the (extended) family members, it means that personal arms showcase their association with the clan.
Where things get complicated, however, is when inheritance kicks in.
First of all, Scottish women are slighly more 'persons' than English ones when it comes to heraldic matters. They can be clan chiefs and can pass crests to their children if they are heiresses - which is a fancy way of saying 'if daddy didn't have boys' And a couple's achievement is generally identical for both spouses, even if coronets of rank are involved.
Further, a non-armigerous husband of an heiress can change his name and matriculate his wife's arms.
So far so good. But we're not done. In Scotland, there is almost always an option for an heir. So if you die single and childless, your brother may inherit your arms. No siblings? No problem, we can find a suitable heir in a different branch of the family tree.
But that's not the complicated part yet. That is when we add hereditary feudal dignities to the mix, which means quatering some shields, and that can be an issue for a clan chief who inherits from an heraldic heiress. In such a case, tradition says 'keep the clan chief's arms as unmodified as possible'. So I'm guessing that Scottish heralds have a few bottles of Ibuprofen available free of charge at the office.
Did I mention that we're not done yet? The Lyon Court is also in charge of legal change of names that indicate dignities like lairdships (got 5 acres of land in Scotland - apply today!). You can have both a territorial as well as a clan designation, so someone's legal name can become the simple 'Joe X of Y and Z', and their kid have (Bob X, yr of Y and Z). I'm going to guess that a lot of government offices (e.g. Passport Office) in Edinburg also keep some Ibuprofen in stock.
Back to actual heraldic stuff. Badges are rarely granted in Scotland, and the applicant needs to show that they are expected to have some 'following' to have one. The English suggestion that everybody should have badges to put on all their stuff doesn't fly there. However, crests are nearly synonims with badges in practice (p. 177).
But this is not the most interesting part of this book. We have two chapters devoted to the use of heraldry in Scottish life, as well as its commercial applications.
On the commercial side, one can make money by form of 'patronage', which is similar to the Royal Warrants to display the Royal Arms in the UK. In other words 'You keep selling quality wares, give me money, and you can show my coat of arms in your business' - probably with some explanatory text nearby.
Also, you can apparently put your arms on the wine bottles your land produces.
On the non-commercial side, there are a lot of uses of personal arms as well as other's arms (as long as the context makes it clear there is no usurpation). An example is for the owners of a feudal dignity to put the Royal Arms above theirs.
When it comes to people showing their personal arms, people are greatly encouraged to do so. This quote is too good to pass:
'The use of heraldic devices in Scotland has been constant, and indeed wholesale, amongst all ranks of armigerous persons, and our heraldry is displayed in every conceivable manner. The cult of "unostentatious affluence" and "contempt of scutcheons", is a product of the crabbed mentality of the industrial profiteer of the English middle class. The vulgar self-consciousness of those who worry about "ostentation" is thus a product of modern class-consciousness, and never had any place either in the Scottish character or the Scottish clan system.' (p. 162)
So, how do Scots use their heraldry?
- Coat of Arms on the side of the car
- Coat of Arms of their friends in the house
- Crest with helmet, a belt-and-buckle around, with the owner's name on the belt-and-buckle (and it hints that the same, without helmet, is fair game for retainers)
- Personal arms all over the house - on the doorway or above the fireplace, on panels or doors, even on furniture.
- On plates, teapots, etc. (ideally, the couple's arms)
- Book plates (full achievement), note paper (crest or full arms)
- A chief's badge (crest, with motto in belt-and-buckle) can be worn by clan members. For other uses, it can be done with the mention of 'Cirean Ceann Cinnidh' (p. 180)
- An heraldic cloak for ladies looked really cool. It shows the impaled arms of the couple.
- Banners of arms at the armiger's house (p.42)
- Ensign/Ensygnye: a full achievement on a flag of the livery colours. (p.43)
- Standard, Pinsel, Pennon, Guidon: restricted to peers, baronets, clan chiefs, etc - pretty much on the same grounds as the badge. They can be used to indicate the leader's field headquarters.
[Edit 22 Feb 2016: Added information about the flags and reformatted]