Paying down LOC

This sounds as though you are "capitalising the interest" on the I.P loan?

Capitalising the interest is good for short-term cashflow, but there is a danger in that you are adding more debt to your financial position, while you hope that some cap gain offsets the extra debt. This is a bit like gambling, and you need to be realistic; life happens. What if the market slumps, or you get sick or injured or you lose your job, or all three?

Many investors don't do bother trying to pay down investment debt because it affects your cash-on-cash return. Idealistically, this is o.k; you put in less money, the investment increases so your return is better. But…

Personally, I believe that you should try to always pay down debt, whether it is tax deductible or not.
Of course, you should try to cut out the non-tax deductible debt first, then start on the the investment  after this as it is tax deductible and costs you less.

At the end of the day, if you continue to pay down debt, you are improving you over-all financial position. Property investing is a business, and one of the biggest causes of businesses going broke is laxk of cashflow – too much debt; too many expenses.

When you pay down debt, your equity will increase, your cashflow increases as you have less debt to service, your ability to service more investment debt increases so you can get access to more finance –  the whole scenario is better for your financial health.

I would only start paying investment loans down if you have paid off all of your non-investment loans first.