What constitutes leaving every 60 days on a 10-year L Visa

Hello,

First I must say your site is terrific. I have learned a great deal in just the few minutes I have perused it. My question is similar to Dann's regarding my wife/partner. For financial reasons we never officially got married. It is a bit complicated. However, we have two children together and have lived as husband and wife for nearly 15 years. I will be working in China (near Hong Kong) and will obtain a residence status through my work. My significant other already has a 10 year L entry permit. What constitutes leaving the country every 60 days? Does HK qualify? Because I can imagine shopping trips there quite frequently.
Thanks very much,
Jim