It's not that bad Jonathan:

8.4 Other environmental items

8.4.1 Fluid leaks
You must check for fluid leaks on all vehicles other than Class 3. You should do this with the engine idling.

A leak of fluids such as engine coolant, screen wash and fluid required for Selective Catalyst Reduction aren't reasons for failure. You should fail a vehicle if a fluid leak creates a pool on the floor within 5 minutes that's more than 75mm in diameter or if there are many leaks which collectively leak fluid at the same rate.

Indeed, I rang my friendly garage about this the other day, feeling a little worried about all my cars and the mot. Especially with oil leaks and emissions.

He told me it has to be a relatively bad oil leak and all my babies should be having no trouble.

The Deuche has recently become leak free pretty much, so that's good.
I have a Mercedes that leaks a bit here and there, recently has been leaking a fair amount of power steering fluid because the reservoir lid seal became no longer available. I found a suitable replacement but it's all a bit wet under there. He said its fine, just wash it off.

Emissions aren't affected, only for those bleeding horrible stinking diesels. (I don't mind diesels apart from having to breath in the smoke when cycling to work.)

So I think we'll be OK.

Diesel emissions are only affected for newer vehicles in that they must retain and have working their emission control equipment and not emit any smoke. All the older more polluting ones can just carry on as you can't retrospectively make them more efficient or conform to later EU standards.

and he has an amusing regime ref maintenance.