What they need to do is save your character, and the Synth status, at the end of every step of a craft. Crafting related buffs (Great Strides, Steady Hand 1/2, Innovation, etc), what your current Progress is, what your current Quality is, what number of Step you are on, everything.

Disconnect? No worries - your stuff is still there, exactly as you left it - except maybe for food buffs or other non-crafting buffs that may have expired while you were trying to reconnect.

Fail 5 Hasties in a row, and pull the plug? No worries - your Synthesis is still there, with all five Hasty Touches failed, when you return.

I cannot see a way that this could be abused, myself.