• Oil composition strongly influences the minimum miscibility pressure (MMP) and miscible-type displacement thresholds in CO2 floods; data suggest hydrocarbon molecular size and extractability govern CO2/oil interactions, challenging earlier reports of negligible oil-composition effects [1], [10], [6].

• Phase-behavior interactions with macroscopic bypassing constrain ultimate oil recovery in CO2 floods; core floods and simulations reveal that multicontact CO2/crude phase behavior couples with bypassing and viscous fingering to reduce sweep efficiency compared with stable displacements [3], [9], [19].

• Mobile-water effects near the displacement front alter CO2 flood performance; AGWIP and related experiments show mobile-water saturations influence residual oil saturation and that foam/mobility-control approaches can improve sweep in certain reservoirs [2], [20], [5].

• Gravity-stable miscible CO2 processes address density contrasts and slug design to maintain favorable gravity segregation, enabling improved heavy-oil recovery; laboratory designs and field demonstrations illustrate practical implementation in carbonate and sandstone reservoirs [15], [17], [16].

• Field-scale CO2 miscible flooding pilots demonstrate practical feasibility across diverse reservoirs, testing slug strategies, WAG-like sequences, and interaction with local geology; lessons come from multiple field studies and pilots [11], [13], [4], [16].