UK Commuting and HMRC
If you're making frequent trips to/from UK either working or "commuting", and/or your immediate family reside permanently in UK, or even if you simply have accomodation kept available for your use on visits, you really need to get advice on your Non-Resident status, or, at the very least, visit the HMRC website and read the rules about the new HMRC definitions of Non Resident. The rules changed very significantly in April this year, the intention being to "tailor" them to an individuals specific circumstances and move away from the previous "blanket" rules which relied primarily on the number of days spent in UK. There are now many potentially very expensive traps for the unwary, and your nieghbour or best buddy who thinks, or sounds as if, he knows all about it, is probably the last person you should listen to (unless he's an HMRC Inspector or Tax Accountant).
On the topic of HMRC not being able to trace your visits to UK, I was advised several years ago that Gen Dec and Pax Manifest copies all find their way to HMRC. That was pre-911 and at a time when electronic information, monitoring and coordination was much less sophisticated than today, so I'd think it reasonable to assume that there's a very high probability that HMRC can trace your visits without difficulty.
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