This will place so much unnecessary distance on an already very long day.
The best route for the 3000s is to use the tried and trusted direction as far as Tryfan, then depending on the walkers stamina and energy, to either use the Glan Denna route to reach Pen Yr Ole Wen, or the energy sapping direct South ridge.
Ive now completed the full distance, five times, and one can only really experiment on differing route possibilities after the completion of Tryfan.
Unless your confident on doing the entire round in under 11 hrs, then swapping and changing the route is virtually destroying any possibilities of a successful attempt in a day.
Navigation in the Carneddau in pitch darkness is far from easy, far harder than on Snowdon.
The entire route from Llanberis or Pen Y Pass, to Abergwyngregyn is near enough 37miles of the toughest walking in Southern Britain.
When i managed my first successful day outing, in just over 17hrs, it was using the quickest direction, from Snowdon to Foel Fras, the route you have decided upon, and that was without stopping, apart from refilling my Camelbak in the waterfall behind Ogwn Cottage.
All my eating was done whilst i was in motion, because i knew a successful one day 3000s could not be achieved in daylight hours if one wasted time scoffing food at a cafe.
I realise most people start early, just as dawn is breaking, but its far better to finish such a huge adventure in the daylight.
Walking around with legs that can barely move, in pitch darkness on top of Foel Fras, is not advisable, especially when you still have nearly six miles further to crawl.
I did finish in the dark, simply because i got badly dehydrated, and was totally spent by the time i reached llewellyn, but all my other successful attempts have been in daylight hours.
All this is fine if the weather is good, but unless you live on the doorstep and can choose the perfect conditions (Cool and sunny), then any attempt at a 3000s