Gareth and Erec: the Same Person?

According to Roger Sherman Loomis in Arthurian Tradition and Chretien de Troyes, "King Loth had a son Guerehes, and one of the adventures of Gueheres, son of Loth, as will be seen, offers a significant parallel to the ride of Erec, son of Lac, with Enide." Loth seems to be a cognate of Llwch (or Loch, Lloch and the French Lac), the father of Erec (whose name developed from Guerec, which has obvious connections to the name "Gareth." Interestingly, Loth and Lac are both kings of Orcanie. Loth's other son Guahries (Gaheries), who becomes the Gareth or Gaheris of Malory, also has many adventures like those of Erec, reinforcing the claim that Gareth, Gaheris and Eric probably have the same origin (72).