I have a UK passport and 3 x ('60' day) Thai tourist visa (from London). I did a border run at Padang Besar recently. However I wasn't aware of the set-up there and I never actually entered Malaysia. I got stamped out of Thailand, walked the 200m to the duty free shop (in what I now realise to be NoMansLand, not Malaysia), had a sniff around there for 10 minutes and walked back over to Thailand. The security guard at what appeared to be the gate separating nomansland from Thailand, looked at my passport and asked me a couple of innocuous questions and then let me through to Thailand-proper where I got a proper stamp back-in for 60 days.
So, on the face of it, everything is fine and dandy. Got stamped out of Thailand, got stamped back into Thailand. I just didn't realise it was another x km to Malaysia so never got stamped in or out of Malaysia.
Am I in the clear, or is there a chance that this will bite me in the bum later ? If it's all A-OK, then why bother schlepping the extra few km to and fro Malaysia at all ?