I don't know the truth from trying a Skinny firmware modem and a Smart Mesh 2 but the Skinny advice just seems wrong. And if is is right then it's stupid.
Edit. From an earlier GZ thread "Ah never mind. I raised a ticket with Skinny and they replied saying the Spark Mesh unit is compatible with the Skinny Smart modem however is not supported from a troubleshooting perspective etc."
Still seems short-sighted. Skinny makes no reference to Smart Mesh units at all in their advice on getting best wifi performance.
For fibre you don't need a Skinny branded modem, you could get $5/mth discount for 12mths by supplying your own Smart Modem. There must be SH ones out there.