interesting
I think that you should always follow your strong instinct and intuition.
For me, IMHO, i think that time is not linear - but it is a useful illusion. As a palmist etc etc, i have had 'flashes of the future' - they generally turn out true, sometimes from a slightly different camera angle.
Do you think you should avoid ALL post life errrrrm ?Pro ?-gressions??? or just this person/ your current clients?
The idea with past lives is we often incarnate with the same set of souls - kinda class reunion thing; or factory batch... so doing a pst life regression may open a can of future worms where your client- hypnotist relationship may be compromised owing to beliefs based on a future existence - ethically a big headache- if your client then thinks you will be lovers/ family etc in 'the next lifetime' or feels guilt for, say, being the person who murders you in a fit of jealous rage - which would make no sense linearly.
[scrub out energy-envelope of the thought there... ;-)]
So i think the idea of future lives is fascinating, but one to tread with caution. I have been lucky to get minimal flashes of past lives from only 4 people i have met - and amazingly, they too have confirmed details.
It is nice to know we dont lose old friends - remembering dying of a lung disease was a bit much, but going over into death was peaceful - I dont fear death. For me, it is just a door, and life one big circle.
One person, who supposedly caused my death in one life, stopped me choking to death in this one - so there we have a rough balance

Past life stuff CAN help you get a handle on awkward energies, stuff that keeps coming back and happening;
It can give you a framework to work with stuff
..but i still think it is the life we are living we should pay attention to. Thank you DT