Be careful while using the VNAV PATH des... if u got strong tail winds during des the a/c just increases the ROD to keep on path... usually increasing the speed... though there is a reversion mode present... but u dont want to go all the way to 335 kts where the reversion mode kicks in ... its too close to the clacker speed... very uncomfortable... ( to avoid this make sure the des. forcast page is filled up)... all the best...