As an examiner I considered the JAA Skill test to be too long and split a number of early tests. There are problems splitting a test as the only real place to split it is at the diversion. This requires a suitable airfield, and if the split is too long, the candidate can find it more tiring than on a continuous test; it also means some inevitable duplication. Having tried it, I now prefer to conduct the test all in one and most students seem to agree.
The old UK system of Nav Test and a separate GFT was a far better way of doing things, and whilst you could still do this under the JAA rules, it can only be done by the same examiner making it much more difficult to arrange.