If you have to fly a heading of 050 to maintain the track of 070 then so be it, as long as you are on the 070 radial what is the problem?
The problem is that the base turn at the end of that 070 outbound assumes nil wind. If there's a substantial wind component blowing across the final approach track, your turn will not end up on the FAT.
Say the inbound is 270, and the wind is 360/40. If you start from the end of the 070 radial outbound, at the end of your 200 degree right turn you'll end up almost a mile south of the FAT, which is not a good place to begin a stabilised approach.
The principle is similar to that of allowing "triple drift" on the outbound leg of a crosswind hold to compensate for the different radii of the turns.