Apologies, my wording was about as confusing as the policies themselves.
Ok, so I looked more into the T&c's of Hiring a car and now have a headache!
this is from Travel Jigsaw:
Collision Damage Waiver reduces the renter's liability from the total cost of the damage to an excess amount, where applicable, unless the renter intentionally causes the damage, is under the influence of drink or drugs, or uses the car in a prohibited or negligent way such as driving off main roads or hiring to other parties. CDW covers liability for damage to the car or its parts. In most locations, windscreens, tyres, undercarriage, replacement locks, replacement keys and towing charges are not covered under the CDW policy. Other exclusions may apply and can differ between car hire companies, so we recommend checking these exclusions with the car hire company when picking the car up.
Theft Protection (TP)
Theft Protection reduces the renter's liability in the event of theft or damage caused due to theft or attempted theft of the car to an excess amount, where applicable. Negligence connected with the theft of/damage to the car may lead to the car hire company requiring the full amount for the cost of the car.
IMPORTANT NOTE
Please check carefully the details of the cover provided by the car hire company. It is not unusual for third-party cover to exclude members of your immediate family or members of the same home address who travel with you, the renter, in the car. Top-up policies will normally be available to purchase directly from the car hire company, or such cover may already be included in your holiday insurance. For peace of mind, we strongly recommend that you, the renter, familiarise yourself fully with the extent of the cover provided with any rental and, where necessary, take out additional cover in respect of your spouse and any children or close relatives who will be accompanying you in the car.
Personal Accident Insurance (PAI)
This optional insurance may be covered by your holiday insurance (please check before you, the renter, travel). If you require PAI, it can be purchased at the car hire counter when you pick the car up.
But still no mention of SLI!
and Cover-more ins only covers excess