When you do Abhyaas with same Sangat, day after day, week after week, month after month and year after year, then there is no need to make an effort to ensure that the Abhyaas syncs. It happens automatically. When one Gurmukh moves to change the speed or volume, others just follow till they fall back to the regular rhythm. There is a lot of Anand in Abhyaas, when all do it in same pace and rhythm. This is why, doing Abhyaas with regular Sangat is encouraged.
The problem arises when Gursikhs do Amritvela Abhyaas alone most of the time or don't do regular Amritvela Naam Abhyaas. Their "Vaahe" and "Guru" normally is not in Taal i.e. either their "Vaahe" is longer or their "Guru" is longer. They are probably fine if they do it alone but when they come in Sangat, their Swaas Swaas Abhyaas does not match with rest of the Sangat and this sometimes causes Be-Rassi.
It is imperative that after Amrit Chhak, one should do Abhyaas in Sangat for at least a couple of weeks to ensure that one grabs correct rhythm, pace and Jugti.
When doing Abhyaas in Sangat one should not try to impose one's own Bhaana on Sangat but should go along with rest of the Sangat. If one feels the need to change the pace of Abhyaas, then one should go loud and slowly change the pace, so that others get time to follow. Some Gursikhs only like to do Abhyaas in very slow pace while others like it very fast. Pace which is too slow can sometimes become boring because it allows the mind to wander. By the same token, sometimes too fast a pace exhausts one quickly, resulting in dampened Abhyaas after short time.
If one wants to be a horse of long race, then it's prudent to go at normal speed and occasionally, if required to tame the mind, do fast or slow paced Abhyaas. The main thing is to bring the mind under control and to listen to Shabad from within.
One should keep consideration for others while doing Abhyaas. Many times, other Gursikhs may get more Josh-o-Khrosh resulting in fast paced and loud Abhyaas. One should go along with such waves of love instead trying to slow them down. If one goes with the Bhaana of Sangat, one quickly realizes that Guru Sahib blesses with more Anand.
If one knows that one is out of sync with rest of the Sangat, for whatever reason, then one should do Abhyaas with low volume, so that rest of the Sangat is not disturbed.
Rest, Guru Sahib controls the Abhyaas environment. What can mortal beings do.
Kulbir Singh