I don't think it looks real. I don't have enough signed copies to know how much his sig has changed, but it doesn't look much like the one I have (signed in 2000 I think), and that was signed in front of me.
The thickness of the pen lines makes it look like someone has drawn this quite slowly. The sig in my book has uniform thickness!
Lots of people on here have more experience in TP's sigs, I'm sure you'll hear more.
ETA I've looked at my second signed book, signed 7 years after the first, and the sigs have changed hugely. So now I don't know - sorry!
It would be helpful if you can provide more info is it from a bookdealer, ebay, or from a private sale, or something like Amazon or Abe and what book title it was as Terry was writing two a year then as I have all the early signatures at the time except one I can check which one he was using then. As such that sig looks suspect.
No experience of Pterry's siggie but some of forgeries. Depending on the type of pen used it is highly unusual for the pen strokes to be totally uniform especially if a pencil, trad ink pen or even a bog standard biro is used. Rollerballs perhaps may have uniformity, but even then you generally see 'pressure' areas. Digital and rubber 'hand-signature' stamps generally are uniform naturally.
So from that PoV your sig is someone's signature. However, I agree that it does look 'drawn' rather than scrawled - especially the bottom curl of the 'T' and at the top of the 'P' and the 3 cross strokes at the end also look too 'studied'. All of the distinct characters curves have a 'coloured' technique (I'm assuming this is an upsized image you've posted) and don't look at all fluid or practiced. So yeah - very likely a fake.
mmmmm concidering all things happening with terry and checking my latest signed book which i know is genuinly signed i would say it could very well be real, im no writing expert but its close enough to my last one for me to think it is, of course theres always that posibilty someone else signed it on his behalf, alot of writers used to do that, oh and i should add yes its a later signature signed on an early book you get alot of people doing that trying to get everything signed by him at events, well you did but not so much now.
I have to say Terry's sig in my signed books changes a bit in each time but I know they're definitely his cos I was there when he signed them. Also the majority of my books were signed long after he'd written them so you cant rely on that as a way of veryifying the sig either.