[James2001]

In taking a PAL SD picture into a HD  raster you need to zoom a bit
to get rid of the half lines that otherwise Twitter with the interpolation.

Funnily enough ITV3 don't seem to do this, as said twittering half lines at the top of the screen are very noticable on their Corrie and Emmerdale repeats!

But seeing as it's otherwise a sharp picture and properly interlaced, I'll let them get away with it

But even then, I'm sure UKTV's zooming on the affected shows is more than is a lot more than is needed to cut that off, with it being zoomed in enough to put captions nearly at the bottom and sides of the frame, it must be around 5%-10%, seeing as it seems to vary between episodes, of the frame being cut off.