I've drawn a graph of a standard off peak hour of departures from Paddington as far as Reading, which is found below for anyone interested. Apologies for the mistakes that will inevitably be in the graph, but I think it is an interesting overview of the new GWR timetable. (Apologies for the poor quality of the picture, for some reason the forum wouldn't let me upload a 2.4MB file, despite having done so in the past.) A few observations (mainly about paths which appear to be unused): xx12/xx13 xx12 - a train could be squeezed in here (125 mph path), but it would only be 1 minute behind the xx10 HEx service at Airport Junction, which is probably not permitted. Pathing time could be added, but then you might as well depart PAD at xx13. xx13 - a 125 mph path could be squeezed in here, and would be 2 minutes behind the HEx at Airport Jn. However, the following service is the xx15 Bristol fast train, so an xx13 would likely obstruct the progress of the xx15 as it slowed for RDG Overall, there doesn't appear to be space here for another path. xx23 - this follows the xx20 Oxford, which calls at Slough (2 minute dwell). Therefore, at least 1 minute of pathing would need to be added to the xx23, plus extra to avoid catching up the xx20 as it accelerates from Slough. Alternatively, a 110 mph path could fit but would have to go onto the slow lines at Maidenhead. xx38 - there appears to be a clear 125 mph path here (maybe even a 110 mph path, although this may impact the xx45 Bristol fast). However, the xx36 on the graph is the Exeter semi-fast, which I believe alternates with a 110 mph Newbury Electrostar; this 110 mph path may mean there is no space for a following path. xx42/xx43 - same as xx12/xx13 xx53 - same as xx23 xx58 - there appears to be a clear path here xx00 - there appears to be a clear path here If the Cheltenham/Bristol/Exeter flight could be shifted closer together, it would appear possible to fit another path in here Presumably some of these paths are used in the peaks. Off peak, I can't really see any use of the potential paths above (there seems to be plenty of recovery space in this timetable, so any extra paths would impact this), so I've just wasted 5 minutes, but it's (hopefully) some interesting analysis. In summary, there are 12 GWR paths (10 calling at RDG, 2 non-stop) and 4 HEx paths. A few questions: Why does the xx07 Bedwyn train have 5 minutes dwell at RDG? Similarly, why does the xx20 Oxford have 3 minutes? Everything else has 2 minutes. Why do some trains take slightly longer between PAD and RDG (for example, the xx07 Bedwyn takes 25 minutes, the preceding xx02 Bristol and xx04 Plymouth take 23 minutes)? Why does the xx40 HEx take 1 minute longer to get to Airport Jn compared to all the others? Admittedly some of these variations could be due to incorrect information on RealTime Trains (although I think this is unlikely).