On macleodgenealogy's entry for Tormod MacLeod: http://macleodgenealogy.com/ACMS/D0022/I2.html they write that:
"Prior to 1974, the common tradition of the genealogy of Clan MacLeod has this Torquil as the second son of Leod. However, there has been groundbreaking (and tradition smashing) work done by Matheson, in a paper published by The Gaelic Society of Inverness, (Vol. LI, pp. 320-337) which calls this tradition into question. Picking up on Matheson's work, Alick Morrison has produced THE MACLEODS: THE GENEALOGY OF A CLAN, Section IV, which presents a different picture of the relationship of Siol Torquil (the Clan name given to the MacLeods of Lewis) to Siol Tormod (the MacLeods of Dunvegan and Harris). This new line was further researched by Major Loudoun MacLeod, and Andrew MacLeod. The result is a second edition of Morrison's Section IV, published in 1990. The old tradition, dating back to Robert Douglas of Glenbervie's THE BARONAGE OF SCOTLAND, 1798, needs to be replaced by this new information, which is reflected in this genealogy. According to the old tradition, the lineage is as follows: 1. Leod -2. Tormod (Norman) MacLeod, founder of Siol Tormod. -2. Torquil MacLeod, founder of Siol Torquil. According to the new information, the lineage is as follows: 1. Leod -2. Tormod (Norman) MacLeod (ancestor to both Harris and Lewis) --3. Malcolm (Gillecaluim) ancestor of the MacLeods of Harris. --3. Murdoch (Murchadh), ancestor of the MacLeods of Lewis. ---4. Torquil (Torcall Og)."
If we go by the old tradition, Dorothy fits into the lineage chronologically as the wife of Torquil MacLeod, founder of Siol Torquil and son of Leod. But with the new tradition, at least on macleodgenealogy, they seem to just be lumping the Tormod and Torquil from the old lineage together into the same person, including their wives (citations include references to both Tormod and Torquil and the only ones mentioning Dorothea all have Torquil as the husband). It looks like quite a mess to me, and I am not sure where Dorothea fits into this new tradition. Are Tormod and Torquil treated as the same person in this new lineage or has Toquil been moved up two generations and become Torquil Og MacLeod of Lewis ? If he has moved then the Ross relationship to Torquil no longer works chronologically as you pointed out, especially is she is the daughter of William II, Earl of Ross.
This is so confusing! Auuuggggghhhhh!!!!!! :-)