Hold RE in Roth 401k?

[Don Ireland]

I've read advice here on BP saying that it doesn't make sense to hold RE in a "tax efficient account" because you "lose all your tax benefits of RE".  I find that puzzling and I'm looking for clarification.  

Sure you no longer deduct things like depreciation but if the house is a Roth asset (purchased using Roth funds), then doesn't that mean that there are NO TAXES from which to deduct?

My plan was to put after-tax-money in my Roth 401k plan and use that money for the downpayment and let the rents cover the mortgage and operating costs.  Having done that, it seems that all rents received and eventual capital gains will be completely tax free as long as I wait until I'm 59 1/2 before taking money out.  And if I DO want to use some of the funds before then, I can take a loan from the plan.