* Kestas, I've never seen a professional shop add AC oil that way (and I've serviced cars professionally for 30 years). You're suggesting to add oil to each component and then close, "button-up", all the connection points before vacating and charging. Seems like that procedure would avoid compressor damage, but it's a lot of extra work. The oil quantities listed in the tech specs are allocation amounts. The oil is put in in one place and then circulates with the freon throughout the system when the compressor is turned on, each component capturing approximately the allocated amount.
* The procedural question came up in the shop and I thought I would put it before a larger audience. After a system is flushed (generally a good idea plus most compressor manufacturers require flushing to validate the warranty) oil has to be added. A load of bubble-free oil through a running compressor can damage the compressor. So I guess it comes down to installing the oil in such a way that it is "foamed" or mixed with the refrigerant before it gets to the compressor.