Would advise against it. Not sure it wouldn't pass an MOT.
Wasn't thinking of doing it James. It just occured to me. If I can, I get tyres for the MGZT off ebay. They start at £170 each new, so if I can get them cheaper, its well worth it. I got a nearly new set of 4 off ebay that had come from a written off mazda RX8 so , obviously, two for each side.( £200. Big saving)
But it got me thinking. You often see a single tyre for sale and there is never any mention of the direction of travel in the ad.
As others have said, i believe if you directional tyres wrongly then water dispertion would be affected as well as possibly grip.
If you see ads and no mention of direction then possibly they can be fitted either way round.
Its usually the tyres that have groves starting from the inner part and moving to the outside that are directional.
What tyres does your MGZT use......i'll have a look at where i get my tyres from and see if they do em
Cheers