I've never seen anyone talk about this before so I think it's better to ask for a straight answer, can Asic miners do double mining? I know its possible on Graphic cards but is it possible to mine two different coins on an Asic miner? For example BTC + BCH or BCD.
What is Merged Mining?
Workers who mine BTC, BCH and LTC can not only receive mining coins, but also ELA, NMC, SYS, EMC, and DOGE for FREE.
BTC Mined BTC and get 2 NMC, 5 SYS, 0.1 EMC, 0.8 ELA for FREE.
BCH Mined BCH and get 1 SYS for FREE.
LTC Mined LTC and obtain DOGE proportionally. (Available in PPLNS mode)
https://support.viabtc.com/hc/en-us/articles/900001530543-What-is-Merged-Mining-