Best Answer - Chosen by Voters
The Story goes according to my Father and Mother who are Dead many Years ago now and who lived at that time. That Collins was the Fall Guy for De Valera. Dev knew he would have to make unpopular Decisions like give something to get something and did not want to appear weak. Dev knew he could not get Total Independence no matter what he did,so sent Collin's over instead of Him. For the sake of Political Expediency and saving his own Political Neck to stay in favour with the Party Faithful he sent Michael Collin's over.
Dev was a Ducker and Diver like a lot of Modern Politicians,they do not make any decisions themselves but organise it so that if a Policy Works they can take all the Credit and if it does not they say I told you so did I not. When Collin's came back Dev and his Friends went off in a Huff and eventually started the Civil War.
When the Civil War was over and the Fuss died down Dev was glad to take over the Irish Free State as Prime Minister after Elections. He was not put out anymore being a part of the Free State/ Saorstad Eireann.