You asked about differences between the two editions of Ancestral Roots (AR7 and AR8) in the first six generations of Line 1. There are some subtle differences although the pedigree is essentially the same. You are correct, the line in AR8 is based in part on a different interpretation of the ASC. Professor Whitelock’s book is an update to that of James Ingram. While I’ve seen both, and the Ingram edition is said to be dated, I haven’t actually compared them. In later generations of AR8 Line 1 the editors simply cite “ASC” so it’s not certain which version is being referenced. Then, the eighth edition has the following sources not mentioned or used in the seventh edition:
ES II, 77 (Europaische Stammtafeln, Band II, Tafel 77 (chart) “Die Konige von Wessex 519-827). An excellent secondary source but only the better libraries have copies.
CCN, 227 (Century Cyclopedia of Names (for handy reference only)).
William G. Searle, Anglo-Saxon Bishops, Kings, and Nobles (1899), 330-351. An earlier source based on the ASC and Asser’s Life of King Alfred. Digitized copy is at: http://www.archive.org/details/anglosaxonbishop00searhttp://www.archive.org/details/anglosaxonbishop00sear
In AR8 under Cuthwine, there is a reference to: Trelawney, D. Reed, The Rise of Wessex. This is a work containing a number of speculations. If you do obtain a copy to read, also read the peer reviews (you can find at least one in JSTOR).
A couple of other differences is that AR8 Line 1 gives dates of death while the seventh edition gives the years reigned (presuming the last date is also the date of death). Also the generation numbering is corrected (AR7 is missing generation 2 which was almost certainly removed from an earlier edition).
One last small point regarding Line 1; both AR7 and AR8 refer to #1. Cerdic as an ‘ealdorman’ which is almost certainly a much earlier mistranslation of the Latin term ‘dux’. The correct translation should have been ‘heretoga’, which is a military chieftain (see H.R. Loyn, The Term Ealdorman in the Translations Prepared at the Time of King Alfred, The English Historical Review, Vol. 68, No. 269 (Oct., 1953), p. 514).Anyway, I hope this helps answer your question.