Short restrictions in air supply piping do not act as predictably as one may think. The smaller nipple may not play a role under most circumstances. The air is compressed and then finds the pressure/volume on the other side of the restriction until the point that the "choke flow" ratio is reached.
Choke flow calculations are fairly deep into calculus and I certainly am not an expert. What it boils down to is that the pressurre on the downstream side of the restriction would need to be almost half of the supply side before there would be any restrictive effect. I do not think you will experience any problem unless you plan on running multiple high air volume consumption tools at the same time, like a DA and a plasma cutter or impact. You just would not normally use the air fast enough for that to act as a restriction.
That is why most smaller compressors only have a 3/8 outlet.
Of course, to gain the greatest volume and delivery regardless of how quickly the air is consumed, opt for the largest fittings. Easier than trying to do the calculus
I just wanted to point out that some minor restriction may be irrelavant based on the actual use of the system.
Incorrect. Once a line is restricted the system cannot pass more air than what can pass through the restriction. Period. No calculus needed.
In this case the 3/8 orifice may or may not impact this gentleman's useage but it will restrict the system's potential.