Chrome,
I don't know the definitive answer to your question..... but if you do a DIR TO the FAF/P and it has an ALT and SPD constraint then the FMGC should take into account a DECEL point so as to achieve the constraints.
Dream - you make a very valid point which reinforces why it is so important to check tracks and distances whe briefing through the FMGC. A good example is the approach into LPFR/FAO (Faro, Portugal). The VOR to R/w 10 has a track reversal in the final approach. i.e. the approach terminates closer to the runway than the final descent point for the runway. It's only about a mile or so and when looking at the displayed plan it looks ok. However if you do not correct it, as you turn onto final a huge 10 mile orbit then appears to sequence the points. If you've just let the aircraft calculate its descent profile you are now about 3000 feet to high.....
I first rasied this issue about 8 years ago, but it doesn't seem to have got through to the database providers yet.......
Remember - check the FMGC in the first place, keep it sensible (TO W/POINT) and back it up with 3 x table and you won't go far wrong.
A4