TBH Ive changed loads of Turbos on VW's. The modern stuff actually run on a film of oil. (if you get the shaft and wiggle it it wil move a fair amount) So sticking a small amount of oil in, whilst it wont hurt, most of it will leak out before you have a chance to finish the job.

Theres not really much point in worrying about the 2 seconds it takes for Oil pressure to build up. Its not like your caining it at that time. What do you think your camshaft journals are doing immediately after startup?