Great Western Coffee Shop

Noticed quite a bit of float in the stops at reading and maindenhead for this service 11 mins scheduled wait at reading and a further 5 at maidenhead:

http://www.realtimetrains.co.uk/train/C42865/2014/05/29/advanced

The reading wait seems logical but the extra 5 minutes at maidenhead seems strange as I can't really see any potential conflicts in other services around it.

It'd catch up with the 18:15 Maidenhead to Paddington at West Drayton if it didn't dwell enroute.  Limited stops, so it probably makes sense holding it at Maidenhead rather than crawling later on.  Shows the difficulty in pathing semi-fasts and stoppers on the relief lines - and the difficulties to be faced squeezing everything in post-Crossrail.

seems pointless to wait 5 mins at maidenhead to then blast through Taplow and Burnham where there were people waiting.

They'd have been waiting for the 18:32ex Maidenhead that runs behind it.  I suppose you could stop the 18:27 there and not hold it at Maidenhead, but that might hark back to when the 18:27 was a 180.  Don't think it makes much difference either way to be honest.

But it is very annoying to have trains pass through Taplow when they have time in their schedules to stop.

I would suggest this even applies on Sundays even on the two track railway. Of course the problem on Sunday is that if the Reliefs are shut trains cannot stop on the main Track too high.! So FGW would have to run a bus!