I felt I had good luck with double drops. But doing the math just now I had just about exactly my expected luck. I needed something like 31 more shards for Han and 40 for Chewie when double drops started.
Over the two days of double drops I spent 1900 crystals -- 6x100, 4x200, plus preloading 2x200 from the day before double drops. Plus 48-ish hours of energy and the two bonus energy boosts. So that's about 1770 energy total. At 16 energy per sim, that's 110 sims. Supposed shard drop rate is 33%, so you'd expect to get a shard drop 36 times in those sims, but since it's double drops you should end up with 72 shards.
Which is just about exactly how it turned out. It was a little frustrating... I had what felt like great drops to start and got Han up to 99/100, then switched to Chewie. Today I finished up Chewie and had enough for four sims left, and hadn't even done the second 200 buy, so I thought, hey I can just do a few sims and get that last Han shard... I spent the four sims I had, and then I was like, well, I had already budgeted this 200, right, so let's do it, and I simmed 7 more times, one at a time, and got nothing! But I was at 14 cantina energy, so I wait for it and sim again. Again, nothing. 12 in a row with no drops! But then a few hours later I had enough energy again so I simmed one more time and got it.
In other words, RNG sucks, but over time it probably balances out. Sounds like you had a bad run of it. Sorry man.
(FWIW, I usually sim cantina nodes 5-at-a-time, which is the totally unscientific method recommended by John from the Galactic War Report podcast. I think it "works" because since the drop rate is 33%, 5 at a time is _almost_ guaranteed to drop at least one, and so long as you get one you feel okay about the world. If you just sim three, you'll notice a lot more times you don't even get one shard. But if you do more than five, then getting one will feel like a letdown. So do five at a time, not because it actually increases drop rates, but because it will fool your brain into giving you good feelings instead of bad feelings--most of the time.)
