alright mate
the dual mass flywheel is fine. IF ....... it was breaking up you would know about it, the chunks of metal flying about in the bellhousing!

i have never heard of this happening
the clogging of the starter is caused by the clutch braking down and fucking up which is what happened to 2 of our transits.

also with the regards to the air leak.
if a diesel engine has a air leak in the fuel system it will be an absolute fucker to start everytime.
i've rescued 3 52 plate transits at work by wrapping cling film tightly around the whole filter housing then it started. these have the duratorq di engines and was due to a cracked/split fuel filter housing. it got them back to the yard then we changed the housings and filter.
with the injectors you cant do the leak off trick like petrols.

luke