1150mm/min is a bit quick for a 6mm single flute carbide cutter. What spindle speed were you using? I almost invariably use about 600-650mm/min and 13000rpm, so I'm slightly surprised that didn't cause problems. It may be more efficient to use a greater depth of cut at the 'normal' feedrate.

It annoys me how inefficient the toolpaths are on many programs... pointless things like raising the Z-axis when it's just not necessary, or moving slowly down to the surface when it could go at rapid speed.