score:7
No traveller clears immigration at a usual internal Schengen border, EU citizen or not. For all intents and purposes regarding travel the Schengen area can be seen as a single country. Almost every time nobody shows their passport or visa and there is nobody they could show them to.
Note that there are some national visas which don't allow travel to all Schengen countries all the time. Those are not checked routinely at the border. However, the national police has the right to conduct checks a few kilometers around the border. In that case buses can be stopped. Checks in trains are usually conducted while moving between two stations (usually they just pick a few passengers for a spot check). Those are however rare.
For reference, this is what a typical intra-Schengen border looks like. Most aren't manned nor are there any other permanent structures or buildings except the sign: