I'm proper plodding along with the Nike Total 90 kits of 2004/05 as well as getting back to grips with a lot of WIP kits... yes, I have a lot of unfinished kits, I just go with wherever my mood takes me with kit making!
Anyway, some interesting notes I found with the Total 90 kits was the differences in the trim/mesh panelling of the player-spec shirts in comparison to the replicas. At first glance, the differences are not obvious, but when I've studied the differences between player-spec and replica shirts, the sides/sleeves do have some rather big differences.
Take for example the Valencia "Senyera" kit I showed you on the previous post. Now, the replica shirt looks like this - the underarm panels are like a rounded square, the side panels are completely meshed, and the yellow piping (you have to look closely) goes all the way to the bottom of the shirt hem...
However, the player-spec shirt had a slightly different construction - the mesh panelling under the arms was a lot different, and went into a curved angled design on the underarms. The yellow piping actually doesn't go all the way to the shirt hem either, instead it gets truncated by part of the side panelling.
Also on player-spec shirts the stitching appears to be all reversed too. I noticed Nike replicas and player-spec shirts of the 2000's/2010's did have quite a number of subtle differences which are hard to see with the untrained eye, but once you've spotted the differences it's hard to unsee them.
Compare with a real player-spec shirt... note this shirt also has a red number panel, where it was used in UEFA competition but not domestically...
Another note is that sizing of mesh panels and stripes on shirts could vary depending on the shirt size too, another matter that has perplexed me when trying to make accurate designs (e.g. size XL can be vastly different to size M).