I don't agree. Yes, heavy as an outright lump, but if you subtract the weight of the normal hub, it's not too bad at all. If you want the simplicity of a compact double, but the range of a wide triple, why not?
Use them in 2nd gear - direct drive - most of the time, but if you want a "smaller granny ring", slip it into 1st. If you want a "bigger outer ring", slip it into 3rd. Use a friction bar-end thumb shifter for the SA - simple and very easy indeed and the chainline is better than using a triple. There are times that instead of using the derailleur, I'll just flip it into 1st or 3rd.