boondoggle \BOON-dah-gul\ noun
1 : a braided cord worn by Boy Scouts as a neckerchief slide, hatband, or ornament
*2 : a wasteful or impractical project or activity often involving graft
No, number 2 was not the surprising definition. Having been a Tiger Cub, Cub Scout, Webelos (the most awkward acronym ever coined), and a Boy Scout (albeit only attaining the rank of First Class), this was news. It appears the current standard Boy Scout neckerchief slide hasn't changed much since SC last wore one, but the Scout catalog doesn't call it a boondoggle. For that matter, none of the available slides are called boondoggles in the catalog. Then again, all of them are basically napkin rings by a different name, and not "braided cords" per the definition. SC is actually hard-pressed to remember ever wearing anything that meets the "braided cord" description, although perhaps the object used for holding Webelos awards comes close.
A bit of further digging indicates that this is not unknown in the archives of Scouting. From an article prepared by the Scouting organization in Great Britain:
In the early days of the Scout Movement in Great Britain, the Scout scarf used to be tied loose knot at the neck and naturally became very creased. However it was known the Americans were experimenting by using a ring made from bone, rope or wood to keep their scarves together. Bill Shankley, aged 18 and one of two permanent camp site employees at Gilwell Park, had the job
of running the workshop and coming up with ideas for camping equipment. He found out about the American rings and decided to try and go one better. After various attempts with different materials he finally made a Turks Head knot - adopted in the days of sailing ships when seamen developed decorative forms of rope work
as a hobby - made from thin sewing machine leather belting. He submitted this to the Camp Chief and, no doubt, the Chief Scout, for approval and had it accepted.
The American rings were called 'Boon Doggles', most probably because they were made of bone, and the name was a skit on 'dog bones'. To rhyme with 'Boon Doggle', Shankley called his creation a 'Woggle'. An article in The Scout on 9th June 1923 by 'Gilcraft', called 'Wear a scarf woggle' made reference to the idea of having become very popular among Scouts who had been quick to imitate the fashion set by the Ist Gilwell Park Scout Troop (i.e.: Wood Badge
A woggle is apparently (at least as originally coined) a wood version of the device in question; the article goes on to mention that Lord Baden-Powell, the founder of Scouting, eventually standardized the use of the term in the 14th edition of the Boy Scout Handbook (called "Scouting for Boys" at the time):
The word 'woggle' was used by Baden-Powell in the 14th edition of Scouting for Boys (1929): It (the scarf) may be fastened at the throat by a knot or woggle, which is some form of ring made of cord, metal or bone, or anything you like. The 13th edition (1928) merely uses 'ring'. The standard World Brotherhood edition used the wording of the 14th edition but put woggle in inverted commas.
Based on this history, the Merriam-Webster definition would appear to be a little more vaguely worded than desirable. The original British boondoggle/neckerchief slide was made of braided leather, but into a ring shape, rather than a lanyard. This would explain the look of the neckerchief slide of today, which may only be molded, but nevertheless simulates the look of being made from rope. As for the boondoggle as hatband? Well, there are some 280-odd Google hits suggesting that, but almost every one repeats the definition from above, and given the history presented by the Scouts, it's hard to imagine that the uniform device crossed over from the neck to the head in any obvious way. The web is hardly the best place to investigate events of the 1920s and 1930s in detail, but suffice it to say that there would have to be more evidence for SC to buy the "hatband" definition.
Left unexplained is how such a useful device could have ended up lending its name to disastrous wastes of time and money. Maybe gangsters paid Bill Shankley to come up with that rather than doing KP?