A method for cutting a blade root retention slot in a turbine engine disk element, the method comprising: forming a precursor slot in the element, the precursor slot having first (40A, 41A, 42A, 44A, 45A) and second sidewalls (40B, 41B, 42B, 44B, 45B) and a base; subsequent to said forming, machining a convoluted profile (24", 24"') into the first and second sidewalls (40A, 41A, 42A, 44A, 45A, 40B, 41B, 42B, 44B, 45B); and subsequent to said machining, passing a rotating abrasive bit through the precursor slot to machine said base, the abrasive bit rotating about an axis off-normal to a direction of said passing; characterised in that the method further comprises: modeling a cutting performance of the rotating abrasive bit reflecting a chip trapping intensity parameter (cp) and a heat intensity parameter; and selecting at least one parameter of the abrasive bit and its passing so as to avoid tool loading where removed chips/swarfs stick onto the bit, wherein the modeling is performed on a computer and includes calculating the cutting performance for a plurality of segments along the axis of the rotating abrasive bit; and for each segment the calculated process parameters include said chip trapping intensity parameter (cp) and said heat intensity parameter, wherein, for each segment, the calculated process parameters further include arc of contact, depth of cut, speed, feed material removal rate, and heat flux, and the feed material removal rate for each segment is calculated as: Z w = D c * feed and the chip trapping intensity parameter (cp) is defined as: cp = Z w L c where D c is the depth of cut, L c is the arc of contact length and the heat intensity parameter is: HI = Q k alpha ∗ L c feed where Q is the heat flux at the tool-work contact zone, k is the thermal conductivity of the material, and alpha is the thermal diffusivity of the material. forming a precursor slot in the element, the precursor slot having first (40A, 41A, 42A, 44A, 45A) and second sidewalls (40B, 41B, 42B, 44B, 45B) and a base; subsequent to said forming, machining a convoluted profile (24", 24"') into the first and second sidewalls (40A, 41A, 42A, 44A, 45A, 40B, 41B, 42B, 44B, 45B); and subsequent to said machining, passing a rotating abrasive bit through the precursor slot to machine said base, the abrasive bit rotating about an axis off-normal to a direction of said passing; characterised in that the method further comprises: modeling a cutting performance of the rotating abrasive bit reflecting a chip trapping intensity parameter (cp) and a heat intensity parameter; and selecting at least one parameter of the abrasive bit and its passing so as to avoid tool loading where removed chips/swarfs stick onto the bit, wherein the modeling is performed on a computer and includes calculating the cutting performance for a plurality of segments along the axis of the rotating abrasive bit; and modeling a cutting performance of the rotating abrasive bit reflecting a chip trapping intensity parameter (cp) and a heat intensity parameter; and selecting at least one parameter of the abrasive bit and its passing so as to avoid tool loading where removed chips/swarfs stick onto the bit, wherein the modeling is performed on a computer and includes calculating the cutting performance for a plurality of segments along the axis of the rotating abrasive bit; and for each segment the calculated process parameters include said chip trapping intensity parameter (cp) and said heat intensity parameter, wherein, for each segment, the calculated process parameters further include arc of contact, depth of cut, speed, feed material removal rate, and heat flux, and the feed material removal rate for each segment is calculated as: Z w = D c * feed and the chip trapping intensity parameter (cp) is defined as: cp = Z w L c where D c is the depth of cut, L c is the arc of contact length and the heat intensity parameter is: HI = Q k alpha ∗ L c feed where Q is the heat flux at the tool-work contact zone, k is the thermal conductivity of the material, and alpha is the thermal diffusivity of the material. where D c is the depth of cut, L c is the arc of contact length and the heat intensity parameter is: HI = Q k alpha ∗ L c feed where Q is the heat flux at the tool-work contact zone, k is the thermal conductivity of the material, and alpha is the thermal diffusivity of the material.