The hot towel issue is a bit more complicated. After 9/11 they agreed to temporary measurements including crewing level reductions. Handing out some hot towels doesn't take very long and is not a problem but there were to be no increase of workload without negotiation. When BA wanted to introduce a hot towel service in WT+ BASSA felt they were trying to get away with another imposition because BA didn't ask them first.
Hasn't the soft product overall been reduced considerably in the past 10 or so years (Club World Sleeper Service, numerous other cuts to the soft product in all cabins), so the introduction of hot towels would not equal a net increase in workload? Also, the configuration of aircraft has changed over time with few pax overall.