I run a multiple spoon programme with my DTs (now 16mo) - they each have one, I have at least one, and they dig in/wave theirs around, while I shovel it in alternate mouths either from a shared bowl I hold, or one on each of their trays.
Tommee Tippee sucker things buy you a bit of time for sticking plates and bowls on the high chair. I am also very relaxed about reserving things that have hit the floor once (it's all good germs, right?!). I just bought some curved metal spoons and fork sets from Boots which help them angle the cutlery into their mouths and have been quite a hit.
It is bloody messy weaning twins though, because you can bet that once your attention is on one the other is wearing porridge on their head.
Mine seemed really slow to get finger food but now they do probably half of breakfast (toast, fruit etc), all of lunch (sandwiches, tomatoes, cheese sticks etc) and some of dinner themselves. I give them something like a couple of rice cakes/breadsticks to nibble on as soon as they go into their chairs to buy me some time checking the temp of food, dishing up etc Then they also get fruit, raisins etc at the end of meals while I clear up. Dishing out a small packet of raisins bit by bit can take ages if you try hard enough!
When I have the energy, I strip them naked and let them just work their way through their 'wet' dinners themselves too - not if they're tired or starving hungry though as then theyre likely to get frustrated. Yoghurt I normally get the majority of it into them using the multiple spoon thing, then give them the pots and a spoon each and run for cover.
Good luck!