What do you consider to be a fat ski? Bushwacker was only talking about a ski in the high 90's in the waist, which is hardly fat by today's standards. And more and more, people find out there are very few trade offs and quite a number of benefits on skiing a wider ski. Especially today's more performance oriented models. I think that if Byron sticks with a sub-80mm waisted ski as his only ski, he is missing out on the most beneficial designs today's ski companies have to offer the average (yep, average) skier.
Even if you went a little narrower than what Bush is suggesting: Like the Rossi Experience 88, Kastle 88, The Elan Apex, The Bliz Bushwhacker, heck even the Head 84 or 94 you'd have a ski that would offer up a lot more performance and comfort in more situations than a hard-snow focused ski in the mid 70's (or less). And, with the performance that is packed into today's skis in the 90's, (the legend 94, Atomic Savage ti, Bliz Bonafide,Ross Experience 98, Nordica Steadfast, the list goes on) and the range of terrain these skis excel at, I cannot see the value in going any skinnier-especially if you have only one ski. Unless you mean to only ski low angle groomers and very small resorts all the time.
There is a backwards thinking being put forth here, that the skinny carving ski is the norm and something in the 90's is a 'specialty ski' for special circumstances. I think with today's designs, the exact opposite is true and should guide your future purchasing choices: The ski in the mid 90's is the more sensible everyday 'normal' ski, and the thinner, carving ski is the specialist tool (for hard snow, hard charging).
With the paltry amount of snow we've had this season, I got tired and bored of skiing carvers and switched a week ago to skiing my fatter skis full time to keep things interesting. Honestly, I like the way they ski and with a few modest adjustments, they perform as well as my thinner skis on firmer snow. And today when the snow turned very spring-like (again! It's been April all season!), they're vastly superior.
That whole skis 'in' the powder vs. on the powder is a little over stated. Even on skis 110mm in width, you don't really just skim on the surface, you are still in the powder (your skis will pop in and out of the snow). If skiing 'in' the powder is really your goal, get a pair of old straight skis--which you won't, and why would you? Nobody really wants to be that IN the powder!
Oh, the Bliz 7.6 mag is a very nice all around groomer carver ski (as much as groomer skiing can be refered to as 'all around' that is). Not very demanding but capable. And, in firm bumps it will perform adequately (if you are one of those carve across the top type bump skiers).