As far as pilots are concerned, the biggest efficiency gains for a company with PBS come from the removal of conflict provisions for vacation and training. Pilots don't care for example, about the gains from ditching a department of experienced employees in favor of a cheap button pusher who largely refers you to the reasons report or to call the vendor or union rep. If the SIG wrote reserve lines there could be massive shifts moving 20% of the blocks to the secondary process, but that's not the case. The raw reserve lines and blocks today represent what the company's magic 8 ball forecaster predicts as the needed reserve coverage. While the point about a one day block is valid, it seems more likely that they'll keep the blocks where they wanted them. After all it's what they wanted and it's not like they knew beforehand who was going to bid/receive what line with respects to conflicts or how they'll handle it. The biggest likely effect of all of this is that the very bottom guys now could have some ugly stretches of reserve as those even slightly above them get a measure of choice with days off. I can see the very bottom guys ending up with schedules that have only one day off between R day stretches for most of the month and one big stretch off because of which R day blocks are available when their lines are constructed. We don't fly the level of block hours as our pax brethren, but there are cases when writing lines like that reduces efficiency because you can't legally use an 'available' reserve due to FAR or contract limitations.