front brake lines and proportioning?

looking at a LA swap this winter and thinking about the brake lines. i see some people run these insanley long flex-lines. this to me doesnt make sense at all. a 30" flex-line (well maybe not that long but long enough to allow full travel) is just waiting to be ripped off. i'm thinkin i'll replumb the front lines to run back to the crossmember and use flex lines to jump to hard lines that will be mounted to the arms themselves.
here is my issue though.
on the OEM system, the front lines are totally seperate from just after the master cylinder.
is this just because they run to seperate sides of the vehicle? or will running a single line to the axle and splitting it to both sides (like the rear does) affect brake effectiveness?
it would be easier to run a single line and split it but does it have to do with the amount of fluid needed for the calipers to work properly?
i will obviously use flex lines at the caliper itself in the new system. just wondering if there is a SPECIFIC reason i cant run it all as one line for most of the length.

thanks guys!

The OEM fronts aren't separate until after the combo/proportioning valve. There's only one line from the "front" circuit on the master cylinder into the combo valve.

There is no reason you can't do as you propose.

Eagle said:

The OEM fronts aren't separate until after the combo/proportioning valve. There's only one line from the "front" circuit on the master cylinder into the combo valve.

There is no reason you can't do as you propose.

Click to expand...

thats what i was thinking, i am thinking the lines are seperate just because it is easier. and makes sense. now i just need to firgure out a location to mount the line-lock.