in the House of Commons, which, it was suggested, justified a place in the Guinness Book of Records. The 1972 Act introduced many new concepts: Rent rebates were to be provided for all local authority tenants. Each local authority had to introduce a model scheme. Rent allowances were to be provided for private tenants whether protected or statutory. These were to be administered by the local housing authority and details of the availability of these allowances had to be entered in rent books. Previously, rent rebates had been introduced on a discretionary basis (in Scotland by the Housing (Scotland) Act 1966), which had led to haphazard, piecemeal and inconsistent implementation. There was also a requirement for more general publicity. Private landlords had to tell existing and new tenants about the availability of rent allowances. Remaining controlled tenancies could be converted by stages. The conversion machinery introduced by the Housing Act 1969 had enabled controlled tenancies to be converted unto regulated tenancies where the property was in, or was improved into, the required standard. The process was speeded up by the 1972 Act, which provided for automatic conversion of all remaining controlled tenancies, whether or not they met the 1969 Act criteria, by stages (intended to be completed in two years) according to the property's rateable value. The earlier qualification certificate procedure was not being implemented as intended. Some over zealous local authorities had been misinterpreting what constituted "good repair" and it would have taken several years to complete the intended progress. Local authorities were given powers to apply to the Rent Officer to consider whether a rent should be registered in respect of any regulated tenancy. The Rent Officer had to be satisfied that the highest rent payable under the tenancy agreement exceeded a fair rent before he could proceed to register a rent. Landlords and tenants were given the right (subject to certain conditions) to apply, jointly, for cancellation of a registered rent. Such an application could only be entertained by a Rent Officer after the expiry of the (then) three-year registration period. The cancellation was only to be permitted of the Rent Officer considered that the agreed rent did not exceed a fair rent. It introduced the right to apply three months before the expiry of a previously controlled tenancy for consideration of a fair rent. This enabled the standard administrative procedures to be completed in time so