I will keep this brief...
The BFT has *never* been successfully thru-hiked as far as I am aware. Three people have indicated they have section hiked it but I have zero knowledge of anybody that has successfully thru-hiked the BFT. That really should be all that needs to be said.
The pdf that MK distributes is rather old. A rather significant amount of the miles of the trail do not exist anymore. Some from fire and some from other causes. Some of what use to be right-of-ways from the timber companies have been revoked - and MK seems to have no knowledge of this or any desire to update the pdf map. The last time he and I spoke he made it rather clear to me that he had no desire to continue development on the trail. I have been the only person working on the trail the last two or so years and I have never provided any data to him - because as stated, he told me he had no intentions of doing any more work on the trail, so no reason to waste my time sending it his way. MK has pretty much moved on in life and has been working on publishing books - I think his second book is soon to be released, if it has not already. The BFT was something he made for himself and for some reason he posted it on the internet making it sound like it was all good and ready to go, when I am not even sure if he has ever thru-hiked it. I know he has section hiked it a couple of times. I am not intending to slam on MK rather just trying to provide insight into the phase development of the trail.
I have been building GPS data on it for at least two years and there is easily another 3 or so years of building GPS data on it before it will be safe to say that a solid route is ready. Already this year I have had to develop a 20 mile by-pass due to a NPS change, and I still have to figure out a bypass through private property that a right-of-way was revoked for. (yet another risk for those who plan on hiking this, or the guy that just finished up section hiking it... he had no idea he was violating private property for at least two days)
For the last few weeks there has been discussion about making an entirely new route change on the Northern most section of the trail. A hiker up in Oregon has recommended a rather major reroute and at this time it is really under a lot of consideration - I am liking what the individual is proposing and I plan on trying to meet with him later this year and sit down with the local government folks he is working with to try to get the trail reroute developed. I share this simply to present the fact that this "trail" is just not really a "trail" yet.
There are many many things that you will be faced if you decide to give the BFT a go on a thru-hiker.
I posted all of my thoughts on an attempted thru-hike of the BTF within this post on facebook. My post did not make a whole lot of people very happy, but every single fact I present are issues you should/need take into consideration.
I have spent more time on the trail than anybody else (including MK) and my personal thoughts are that this trail needs another five or so years of development before it should even be listed anywhere on the internet as a "hikeable trail". You and your husband have a pretty good deal of off-trail experience and I think this trail could put the two of you to a test. Take on the BFT if the both of you feel like a new challenge in your hiking career, but if you are not up for a challenge, might want to hold off for a few more years as we get it developed. The website that MK put together makes this trail sound a whole lot more viable and ready to be hiked than what it is.
If you guys do decide to give it a go, contact me and lets make sure we get you some emergency contacts to be able to get a hold of folks via a SatPhone for if you need to bail out. SatPhone is pretty much the only way to communicate from a good percentage of the BFT - as it goes right through some of the most remote places in America at this point in time. I can get you a contact on the southern end and at the northern end, but anywhere in the middle and on the final sections there is just nobody. Three towns along the trail but nobody in them has been willing to be trail angels. Middle of last year I spent two days going through the two southern towns trying to find trail angels and nobody was willing. If you guys have the ability to drive about 200 miles and put down some caches that could greatly aid in things. The way I would plan to thru-hike it involves four caches. Doing so is going to reduce the need to carry 7-10 days worth of food, down to a more ideal 4-5 days worth of food.
I spent eleven weeks last year attempting to find a starting route that would not require the hell that is Mt. Linn as a starting point. Pretty mountain and all, but a horrific location to start a 400 mile trail. I have spent another three weeks so far this year doing further scouting of potential starting points and routing. I have been trying to get together with a non-profit group of horse riders that are doing authorized trail development along the South Fork Trinity River. They seem to be able to be the best source to help with trying to develop a more viable starting location, yet still be able to take in a fair amount of the first three sections of the trail. I have no idea when this is going to happen, but talks have been progressing.
Would I love to see somebody successfully thru-hike the BFT? Heck yeah. I would even be more excited if you/they took along a high quality GPS (ie: Garmin 62 series) and be willing to share your course data with me to combine with all that I have. What I have been doing is when I know that a specific section of trail is going to "work" for the decade ahead, I hike it in both directions in order to acquire as accurate of GPS data as I can. But even so, having somebody else provide their own data would be really great. At this point, there are a fair number of sections where a hiker could go one way, or a whole other direction, and still end up in the same spot. The more of these different routes I can combine together will make it all the more helpful to decide on a final path to submit to the government agencies and timber companies, who get the final say.
Anyway, that is keeping it short at this point.