I believe the reason that the second bridge has two whites instead of one is because they're not internally tied together, so that shouldn't be a concern.

There are two other things that occur to me:

1) Some surge strips, those with 'noise filtering', can reduce the strength of nearby X-10 signals, and your use sure qualifies as 'nearby'.

2) The bridge bypassing the surge strip might also reduce it's effectiveness as a noise filter, since it's being used to carry high frequencies around the strip.

Maybe someone more familiar with X-10 and surge/noise filters may be able to shed more light. Anyone?

Larry
www.fineelectricco.com