I spend most my ice season on lake Erie catching steelhead not running bobbers works but with two rods about 20 feet apart I find I'm constantly staring at the rod tips for a bite when I use bobbers I can just look for the bobber tip and move onto the next rod running 2 rods and 3 jawjackers really keeps you busy
When fishing deep water, a bobber stop can be set at 5 or 6 feet so you know when a fish is close to the hole, especially when fishing dirty water.