So I know we usually don't do drinks with odd measurements like parts and jiggers, but turning 2/5 of a 1 1/2 oz drink into ounces gets silly real quick - 3/5 and 3/10 of an ounce is hard to measure. The OP asked how I'd scale it up to a 3-4 ounce drink, and my best guess would be to swap the vermouth and gin amounts, so: 1.25 vermouth, and a fat 1/2 oz of gin, brandy and Angostura. Thanks,  Zachary

Thank you for the suggestion. It seems to work well.

I don't follow. Why would you swap gin and vermouth here? That changes the flavor profile.

If you use 1.5 oz gin and 0.75 oz of everything else, you'll get the same flavor in a drink that comes in at 5.4 oz (after dilution).

Using 1 oz gin and 0.5 oz everything else comes in at 3.6 oz (within the request, but small for a modern drink).

Either seem "easy enough".

I think Mr. Pearson's switch allows the drink to be enjoyed as a sipped cocktail better, notwithstanding it subdues it and changes it. If the original brisk "knock-back" is desired on a standard scale (for the sake of experiencing  history, perhaps), 1 oz Gin, 1/2 oz of each of the rest might work, though I've had barkeeper friends suggest tampering with the ratio, adding a dash of lemon or syrup, etc., which might speak more to their personal tastes (i.e., toward more punch-like "balance," or else challenging the palate, etc.). One even wanted to frame it as a Negroni riff, brandy and bitters replacing Campari.

Just doubling the amounts as written leads to a drink that's 2 ounces of 80 proof spirit (and more if you're using bonded brandy) that's balanced by 2 teaspoons of sweet vermouth. That just seems unpleasant, which is why it's a 1.5 ounce shot as written. Swapping them makes a drink that's equal parts gin + brandy and sweet vermouth with a good amount of bitters. Thanks,  Zachary

Thanks for the explanation. Seems reasonable.

I've since had both versions as short sippers (though Butchertown, rather than Sacred Bond). I tend to enjoy bitters-heavy cocktails, but both variants are so Ango-dominant that I don't personally register either as being significantly "more balanced" than the other.

Assuming bonded brandy: after dilution, the original recipe is ~26% ABV, similar to other spirit-forward cocktails like a De La Louisiane or a bonded Manhattan (though a bit less sweet). The inverted recipe is ~23% ABV, closer to a Martinez or a Hanky Panky.

I curated this to conform to the Straub version for a couple of reasons: (1) It's the earliest and best of the three sources (2) A jigger is 1.5 oz, and even though the fraction conversion is wonky, it's a lot better as a 3 ounce chilled drink than a 5 ounce warm drink. Thanks,  Zachary

Sound curation, though I'll side with the later recipes as far as stirring rather than shaking this. 

(And call me crazy, but I might prefer the room-temp version.)

I was familiar with the Straub recipe, but I believe that found in the Old Waldorf Bar Days (published long after the bar manual was written) to represent the earlier form, that is, a stirred, room temperature drink. It has been quite successful at parties.

Looking again at the older sources, I'm wondering if the cherries here are meant to be shaken/strained (Straub) or stirred (Waldorf)--that is, incorporated into the drink at mixing rather than added as a garnish at the end. 

Also, this needs a dry Madeira -- no Bual or Malmsey. I did this as 1 1/4 : 1 1/4 : 1/2 with Sercial on the menu at Loyal Nine and with Verdelho at home. I've also made the room temperature/no ice version from The Old Waldorf-Astoria Bar Book which makes good use of the Maraschino's sugar to balance the drink instead of dilution + sugar.

1/2 lemon, 1/4 tsp sugar

Tasty!