Who writes tenancy contracts?

I've been given a copy of the tenancy contract that the lettings agent for my new flat will expect us to sign in a few days time. It's seven pages long, and full of stupidly long sentences that make no sense. Here's an example:

TENANT'S OBLIGATIONS

(d) Keep the.(sic) interior of the Property and all fixtures and fittings therein in the same good state and condition and repair as it was in at the date hereof (fair wear and teat (sic) and damage by accidental fire or other risk insured against by the Landlord only excepted unless the relevant policy of insurance shall have been rendered void or voidable or payment of the whole or part of the insurance monies refused in consequence of some act of default on the part of or suffered by the Tenant) and immediately replace any broken glass

Huh? There's also an even longer clause:

(n) Permit the Landlord or the Agent with or without workmen and others upon giving reasonable notice (except in case of an emergency) to enter the Property at all reasonable times during the daytime for the purpose of examining the state and condition of the interior of the Property and of the furniture equipment and effects therein and thereupon to permit the Landlord or the Agent to give to the Tenant notice in writing of all dilapidations wants of repair, cleansing, painting amendment and restoration to the Property then found and for which the Tenant is liable herein and by such notice to require the Tenant to repair, cleanse, paint, amend and restore and make good the same respectively within one month from the service of such notice and if the Tenant fails to execute the afore mentioned (sic) work within the said period of one month then permit the Landlord to enter upon the Property and execute such work at the reasonable expense of the Tenant and pay to the Landlord the reasonable expenses of any such work upon demand on a full indemnity basis

Unsurprisingly, it's the two most contentious clauses (damage to property and landlord visits) which have the longest, most convoluted sentences. Wording such as this has no purpose other than to confuse the tenants and to keep the legal people in a job. The language used is neither precise or clear, and uses archaic forms, sub-sub-clauses and lists so often that it could be a spoof. The contract hasn't even been checked for errors - there are random full stops in the middle of sentences, typos, and even numbering errors. The funniest typo is in this sentence, which is already pretty hilarious:

LETTING PROVISIONS

(f) Masculine includes feminine and singular includes plural and mouth means calendar month

How's that for a way of getting around the he/she gender neutrality problem?

The rest of the contract is fairly boring, aside from these odd clauses (which I've translated into plain english):