In an article on Cottages and Farmhouses by Rosemary ffolliott mentions that "In pre-Famine days almost every house had a spinning wheel for making yarn, but this practice was largely discontinued (except in flax-growing areas) after 1850.
In Irish Ancestor Vol III No 2 (1971) in an article on Women's Dress in Ireland 1680-1880 by Rosemary ffolliott she discusses an engraving of a Girl of the County of Wicklow engraved in the 1780's she is portrayed "busily engaged knitting a sock: this was an endless female occupation, although strangely knitting was not used as a means of making other garments." (p88) the sock appears to be knit in the round and has just turned the heel, the colour seems to have changed from the foot to the heel, possibly indicating a different wool used, possibly coarser or thicker wool at that stress point.
In an article about Emigrating from the Limerick Workhouse 1848-1869 by Dr S C O'Mahony (Irish Ancestor Vol XIV no 2, 1982) discusses the fact that in 1848 some 750 inmates of Limerick Workhouse, largely girls, emigrated to several countries. There were three work schemes. One to New York (103 people, 10 male adults, 75 female adults and 18 children, where adults were anybody aged 15 or older), one to Van Diemen's Land (50 girls) and Quebec (112 girls under 25); they were bought an "outfit" having to take their own bedding and cooking utensils) this outfit consisted of "2 night caps, 1 pair of shoes, 1 gown, 2 combs, pins, needles and thread for sewing, needles and 1/2 lb cotton for knitting, 1 flannel petticoat, 2 aprons, 1 bonnet, 2 shifts, 1 wrapper, 1 shawl, 1 brush, 2 towels, 1 neck kerchief, 2 pairs of stockings, 2lbs of soap, 1 prayer book, 2yds of calico, 1 scissors, 1 canvas bag." I would say that the quantity, and the fact that this is only about 220g of yarn that this was probably fine yarn and fine needles.
In an article "Shall these Bones Live" by Rosemary ffolliott she talks about a famers wife "She too often spun yarn for sale, or got her elder daughters to do it, and she and they would knit all the socks for their menfolk, as well as turning a useful hand to the making of clothes."
In the article by Ms ffolliott Men's Clothes in Ireland 1660-1850 she briefly mentions knit stockings worn by men with knee breeches in 1783 "doubtless kntted by his wife".
From much of this it would appear that woven cloth was common and used in the main for clothing. Alice Starmores point that the Aran Knitter was a seamstress may have been as much that the woman who designed the garments was familiar with cutting and sewing garments and not that familiar with the potential of knitted garments. All of this points to Knitting being a relatively new and relatively underused skill in Ireland. A person familiar with how woven garments were put together would be inclined to think of garments as something which was designed and created in pieces and then sewn together.
The evidence also says that wool, cotton and linen thread was available fairly readily (silk would also have been available as Huguenot weavers brought in silk weaving and would have had silk thread, but this would have been beyond the price range of most people, and probably to fine for most knitters. The evidence also points at fine knitting, and while the knitted garments would only have been socks, there may have been domestic knitting as well in the form of doileys, bedspreads, and other such items.
This is an interesting topic to pursue, I would like to find more.
(edited for a minor correction)