There is a Leinster dialect if one considers the natural surviving pronounciation of placenames and a modern excellent speaker of Irish with a natural Leinster phonology. That is, to combine a word perfect command of Irish and native speech (plus accent) of one raised with local speech, be it English, hence acquiring the inherited phonology of Leinster (via English).
What might be felt to be a peculiar word-stress can be heard amongst some young speakers on Raidió na Life, but it is not peculiar when it is viewed alongside the natural pronounciation by some in the farming community of local placenames in rural south county Dublin.
For a great collection of references, go down on the Ciarán Ó Duibhín list to sources at no. 6
http://www.smo.uhi.ac.uk/~oduibhin/oirthear/biblio.txt Particularly:
* Piatt, Donn S.:
"Gaedhilg na Midhe", An tUltach 14:7 (8/1937) 5 (Tomás Mac Eochagáin).
Piatt, Donn S.:
____: "Giotaí de Ghaeilg dhúchasach na Midhe", An tUltach 29:6 (6/1952) 11-12.
And more interesting:
Laoide, Seosamh: "The Leinster dialect", An Claidheamh Soluis 12:40 (10/12/1910) 21; 12:43 (31/12/1910) 5-6; 12:48 (4/2/1911) 5-6.
Piatt, Donn S.: Gaelic Dialects of Leinster (1933) (inc. South Dublin, Wicklow, Kildare, Laois, Offaly, North and West Wexford, Kilkenny, Carlow; North Dublin, Westmeath).
Piatt ____ [Ps. Laighneach]: "Áth Cliath is Cill Mhanntain", An tUltach 10:5 () 6; 10:7 () 4.
Piatt ____: "Gaeilge na Mí", An tUltach 44:9 (9/1967) 9-10.
Williams, N J A: "The Irish language in County Offaly", Offaly: history and society (c1999).
If I were from Dublin, I would delve into both Rinn na Déise and East Ulster plus taking Cín Lae Amhlaoibh instead of television as a night-cap.
As I see it, I have on very few occasions listened to what I consider a Leinster dialect from one or two excellent speakers.
I myself pronounce a few words of it now and again any time I utter for oldtime's sake 'Baile Boch' instead of 'Baile Bocht' if I'm in the area. One can see it, in petrified form, on the street signs at Ballybough road.
Slán go fóill.