I'm afraid I can't as I am getting this info from an expert in the Fair Deal scheme. The HSE has been provided with a table by the Department of Health to calculate the value. It seems that someone is splitting hairs here but that is the scheme.
I spoke to the HSE and they confirmed what you are saying. They said they would not look at the asset if it is just a "right of residence" but would consider it if it is a "life interest"
I asked for elaboration on the definition of these terms and she said that with a right of residence the person is not entitled to any thing when the property is sold (ie has no ownership). Under a life interest the person owns a portion of the property and is thus entitled to a portion of its value under a sale.