Scaredypants – you need someone who has just spent £100 at CRC, chosen to use the XMAS50 code to get this offer, instead of the other £15 off offer, who then choses not to spend another £100 to use their new voucher.
IMHO, only people who are intending making another purchase will use this code, as there are other direct discount codes available otherwise.
So really, you are looking for someone who has changed their mind on the second purchase.
Ive just used this – X0 crank reduced to £199, used the voucher for a Hope Ceramic Hub effectively for £30!!!!!