the ratio between the rate on Ni and Ru at 30 bar, and 2) the ratio between the rate on Ru at 5 bar and 30 bar, to gauge the relative importance of the two pathways. Table and Figure show that increasing substrate branching level leads to increases in both indicators, i.e., the relative importance of hydrocracking to hydrogenolysis. The conclusion is also supported by the lower (C2 + C3) / C4 value with more branched substrates under identical conditions on Ru (Table and Figure ). It is expected based on previous studies with small-alkanes, as 1) hydrocracking mainly proceeds through 3 C + intermediates (type-A β-scissions), and less branched substrates require more extensive isomerization prior to C-C bond cleavage, and 2) 3 C-x C bonds are less reactive than 2 C-2 C and 2 C-1 C bonds in hydrogenolysis due to their high steric hindrance limiting the ability to access the most stable TS. ), further emphasizing that hydrocracking is more favored with more branched substrates. The substrate-dependence of the two pathways explains why in Figure , the bifunctionality of Ru/TiO2-A-SG does not lead to superior performance in LDPE upcycling: the contribution of hydrocracking is minimal with LDPE, and Ru/TiO2-A-SG has mediocre activity/selectivity in hydrogenolysis (will be shown in detail in a separated manuscript). We note that Ru/TiO2-A-SG yields higher fraction of branched alkanes from LDPE than other Ru catalysts with similar CH4 selectivity, but the regioselectivity of hydrogenolysis predicts the two parameters to move in sync. This is because branched alkanes can also be produced on Ru/TiO2-A-SG by isomerization on BAS. The close examination of C10 products from squalane offers further mechanistic insights.