No, BarPeriod 1 is not handled differently. It's however possble that the price functions return other values as in raw data, due to sampling. Bars are aligned, raw ticks aren't. For instance, if you have a price tick in raw data at 08:00:30 and the next one at 08:01:30, the 08:01:00..08:02:00 bar is sampled from 2 ticks.

There are also no bars skipped AFAIK. Maybe you mean the lookback period?