From everything I know, any kind of nipple stimulation like this will trigger your body to produce more milk. So, even if your LO isn't actually drawing milk, the sucking will send the message your body needs more milk and, thus, increase production.
From personal experience I'd say yes. It did for me anyways. LO had a couple really fussy days where he was attached to me all day comfort sucking and I definitely noticed an increase after.
Yes, it will. All suckling helps. This is another side to the recommendation by LCs to delay use of pacis. It's sucking that could instead be used to fine tune the milk supply.
The '24 hour cure' for any problem with supply or weight gain is to be off your feet with baby for 24h, with food and drink brought to you, and constant access for baby to nurse.