The figures quoted show reasonable growth West of Salisbury for many stations in the region of several thousand. However, growth isn't the key factor if the single three carriage trains are already crowded to start off with.
What growth there has been - in some cases the figures were negative in case you have already forgotten - is, as tbtc pointed out when posting, below the national average over that period in most cases. Unlike what happened over the same period in other parts of the country.
I don't object the franchise going "off piste" to Frome etc. I do object to them squandering diesel sets on electric diagrams and giving them away to other operators when there are people standing in the vestibules. I suspect the artificial revenue costs of running additional carriages (in terms of track access charges etc) may be putting them off resolving the situation satisfactorily.
The sets with GWR and EMT were not 'given away' to other operators - they are being used by other operators rather than sitting in Salisbury depot, which is why they were released from SWY in the first place. If the SWT fleet was struggling to cope with demand on WoE services as you keep claiming, then they would not have been available for redeployment in the first place, nor would SWT be using dmus on electrified lies, or adding extra services off the core route - though you don't mind that...:roll::roll::roll:
Without going through them indetail most (if not all) of these look be in marginal time where they would be unable to make any difference to peak capacity into / out of Waterloo.
Until his most recent post, about afternoons, yorksrob had not said what time of day he had encountered problems but his beef is what is happening
nothing was said by hime about east of Salisbury in the peaks, when crowded trains aren't exactly a surprise, like any service around London.
I would agree there may be some scope to withdraw these and leave this in the hands of the GW franchise holder. However some may value the direct service that SWT offers to Bristol.
They can't withdraw the Bristol service, it is a core requirement in the franchise for the whole term. The Somerest extras are experimental and could potentially be ditched at the end of 2018.
Granted it was probably an ORCRATS raid to start with but those passenger numbers suggest the 'raid' has actually done more than that.
The hand of Orcats raiding is all over this one - traffic at Warminster actually fell in 2015-16, after strong growth between 2012-13 and 2014-15, which probably helped attract SWT's interest. Similar growth spurt at Westbury, and still growing there in 2015-16, and who wouldn't like a few coppers from Castle Cary's Glastonbury Festival week? Frome and Bruton have both grown consistently over the period.
Interestingly, I recently compared the cost of an off peak return from Bristol to Gatwick via Clapham Junction (SWT and SN) and it was £62 odd and with GWR via Reading, it was £227, IIRC.
You weren't looking at an off-peak GWR fare - the Anytime return is £221...
For whats its worth, SWT have been restricting their autumn/winter/spring fares on-line promotions to start from Yeovil Junction due to a stated "lack of capacity" West of there - thats SWTs words, not mine.
Promotional fares are used to fill seats on service where there is spare capacity, so if trains are well used, they won't bother offering them. Ryanair don't offer 5p seats on flights where they know they can sell them for a lot more, nor do TOCs offer lots of cheap advances at busy times.
Aren't GWR meant to start running a Devon Metro service to Honiton soon or is that dependent on the 166's being cascaded to SPM and Bristol area?
Anyway if GWR do the Devon Metro to Honiton, that would then allow for the minor stations between Honiton & Central to be omitted by SWT (or whatever their successor is this particular week) meaning faster journey times for those to/from London.
The Devon Metro plan aims for a half-hourly service as far as Axminster, not Honiton, and requires a lot more than just more GWR dmus - in particular an additional passing loop would have to be built at Cranbrook or Whimple. And it would rather defeat the point of increasing the frequency if the London services then only called at Honiton and Axminster.