No offence, but the last thing I'd do is chuck that stuff ˆˆˆˆˆ into my engine!!

Head gasket failures are rare on TDCIs to be honest. What does the smoke smell like? If it smells really diesely then it's not water! Quite a few smoke in the morning as they can overfuel on cold start and chuck out a big lungful of white smoke.

It does sound like it's loosing a lot though. Is there any sludgy mayonnaise on the inside of the oil filler cap? Or any oily gunk in the header tank? If it's the latter the oil cooler can leak, and cause oil and water to swap places.

I'd also consider replacing the header tank cap before doing anything drastic - just in case it's letting water out once pressurised.

Are you sure it's water around the injectors and not diesel? Smell it!!

If there's a wet residue on one of the boost hoses, then it's probably a split hose, Does the car make a 'whoosing sound' when it comes on boost? The EGR-intercooler hoses split for a pastime.