Interesting. Indeed, are your extensive comments about this topic in the thread with that TL?
They are indeed. The gist (and in this TL the Central Powers won in 1914 due to Britain being preoccupied with Irish affairs) was:-
Certainly the War had a radicalising (some might say a coarsening) affect on Irish politics that in TTL would be avoided. For instance:-
1) The social pressures in Ireland were somewhat heightened by the U-boat threat making emigration to the USA, Canada and Australia less viable 1914-18. Didn't happen TTL.
2) The USA never entered the War so unlikely to have adopted Prohibition. Apparently this had a significant social effect in Ireland as a lot of Irish emigrants to the USA had gone into the drinks trade. Some had to close down and some had increased overheads (in bribes and paying smugglers I would imagine!) so less "money from America" and "send the lad over" OTL than TTL.
3) On that front, it is impossible to read a history of the (legal and licenced) Irish whiskey industry without reflecting on what a law abiding bunch they were. They tamely cut back production and closed stills following the closure of their greatest export market rather than finding themselves a lot of new "agents" and "customers" in Mexico, the Bahamas and Canada. As a consequence the number of people in skilled employment in Ireland actually
fell during 1919-32. Won't happen TTL. And the Dunville heirs won't have been killed in WWI, so the Royal Irish Distillery may not close down in 1941.
4) No wartime overproduction of shipping so not so much of a post-war slump. Sectarian tensions in Belfast in the late Teens and early Twenties were heightened by layoffs at Harland & Wolff and Workman & Clark and by attempts by the Protestant community to ensure that these fell disproportionately on Catholics. So tensions in Belfast slightly lessened TTL.
5) Less encouragement to physical force nationalism from foreign intelligence services and the shadier and more deniable elements of diplomacy fishing in troubled waters TTL than OTL. Germany achieved most of its foreign policy objectives in 1915 so is now a satiated power and probably quite conciliatory in its foreign policy towards Britain. Austria-Hungary will, having seen off Russian encroachment into the Balkans, be inward looking and concentrating on internal reform and constitutional and political settlements. Neither Kaiser Wilhelm nor Kaiser Karl will have much sympathy with militant separationism or Republicanism. The Irish have done their job keeping Britain distracted at the crucial moment and can now be discarded. Russia and France have seen what happens when Britain is distracted by Ireland and didn't enjoy it. Any hope of recovery, let alone revanche is dependent upon Britain being at best supportive and at worst acquiescent. Paris and Petrograd will
not want to risk pushing Britain into alliance with Germany. Spies being spies, foreign agents will probably use Irish Republicans as sources of information on Royal Naval vessels in Cork Harbour, submarine trials off Skibbereen, what the RNAS are up to at Shackleton Barracks and what the new Royal Air Service is at at Aldergrove and Baldonnel. But they will only be providing money and not arms or military training.
6) With no involvement in the War, the USA will still be quite inward looking and the Irish-American lobby still isn't quite the political force it will later become. The trickle of American money OTL only became a flood after the executions post the Easter rising. Which didn't happen TTL.
7) A lot of the most pro-British people in Ireland OTL joined up and were killed/maimed/disillusioned by the callous incompetence of the British military command. TTL they are still alive and well and running the family business or farming in Wexford.
8) The English tourist trade collapsed 1914-18 OTL. And didn't revive much 1919-23 for obvious reasons. TTL it didn't.
9) WWI provided all sides in the OTL War of Independence and Civil War with men with military experience and desensitised to violence -Black and Tans, pro-Treaty and anti-Treaty and IRA. TTL not the case.
10) Casement not seized as a spy TTL and will have added his voice to those of Redmond, McNeill and Hobson. He didn't support a rising with token German support so he won't support a rising with none whatsoever