I find the push for Gaelic a bit ironic, because it entirely ignores the equally strong Scandinavian influence in most of the parts of Scotland Gaelic is pushed. Scandinavian may not be spoken but was via Norn in Shetland in living memory and is reflected in the genes and intonation of speech of much of the population as well as at least as many placenames. Any island ending in "ay", "ey" or "oy" is a Scandinvaian name, because that's the word for island in most Norse languages. e.g. Colonsay, Scalpay, Oronsay, Taransay, Scalpay, Raasay, and so on. And on Harris, it seems to me that a lot of the Gaelic names on roadsigns are simply translated phonetically from Norse, not Gaelic. e.g. Bearnaraigh (Berneray), Fionnsbagh (Finsbay), Pabay (Pabaigh), etc..
But Norse doesn't fit into the SNP, pro-independence culture and so is ignored, and Gaelic pushed in its place, which is almost approaching ethnic cleanings of part of Scotland's history.
However, that may change, as since Ireland' economic woes, Salmond is no longer telling Scots they must be like the Irish, but has now told them to be more like Norwegians. So perhaps we will see trilingual roadsigns?