I have seen those &&&$ diagrams in texts too, many years ago. You cannot make a triac by connecting two SCRs like that- think about it- how is the "top" one triggered? It's not an equivalent to the triac structure at all, unless the gates are ignored. See the gate structure below:
In your circuit, the gates will break down with reverse voltage (maybe -10V) then the opposite SCR turns on.
You can connect an opto-triac between the two gates (and diodes across each gate to cathode to conduct when reverse gate voltage is applied) and turn them on like that, or use a triple coil pulse transformer (two secondaries) to trigger both gates at once.
And yet another way to do it, which I recognized on the "cited site".
Around 1977 a professional rock musician buddy asked me if I could make a chaser. 2.4 kW per channel , bidirectional scan, 8 channel chaser with ZCS control, variable sequence speed , direction and drum beat sync sound activated. It took me a day on the weekend and I used discrete CMOS detected ZCS and drove the Triacs with hand wound mini coils. The little board was just wire-wrapped with 8x 25A triacs. It all worked fine until their tech decided to flash 1kW floods at the optimum rate so they drew 5kW pulses. Hey Tony, the darn Tech burnout the chaser... 5:1 repetitive surge currents.