As I said before, we will do anything we can to help you. However, your question about going via SND is a little more complex. On your original route via CLN towards COA you are remaining in effectively the same sector airspace (the group known as East). So they are able to cope with all the vagaries of your route with just verbal coordination if they are split (more often than not they are all on one sector anyway).
If you go on the other route towards DET then you are crossing across several sectors, and you may well be close to the traffic for LL. Bear in mind that within 20nm of DET at the levels you are talking about there are three or more different sectors.
Also, as you route southbound you will be changing from TC North to TC South, who sit on opposite sides of the room. Thus coordination is more difficult, but not impossible.
If you take a look at the airways chart for that area and draw a line from EGMH to EGMC to LAM, then a good rule of thumb would be that if you remain East of that line then your weather avoidance can generally be handled easily (although you will be beneath CAS at FL70 once SE of EGMC), and to the West of it it gets more complex.
If you want to go via DET, then you would be better to file DET-DVR-KOK and then the plan will be easier to amend and the CAS will be down to a lower level.
Ref downgrading the service:
I meant that if your decision to take a route around weather will take you outside CAS temporarily then we are obliged to downgrade the service to RIS/RAS until you rejoin. If you are going to be outside CAS for a long time (eg SND-COA at FL70) then you might well find that controller workload/proactiveness/general apathy might well mean that they are unable to offer a service and will ask you to contact London Info and then get a new joining clearance.
All in all, I suggest you go via CLN and avoid to the East if you need to!!
EDITED: to correct a spelling mistake, but also to put EGMH in instead of EGMC twice!
Last edited by eyeinthesky; 17th Jul 2005 at 09:18.