Search this forum for how many used your approach and puffed their batteries. Dare ya.
I have seen them all too and in every single case it was due to user error. And BTW, there are many other experts out there. I don't claim to be one and never will because I learn something new every day.
One of the many other experts in this field in this field is
Nordkyn Design. I have read other parallel top balancing guides and they mostly agree with each other.
It doesn't take an expert to properly parallel top balance cells. There have been many who have posted their own experiences, mostly good, some bad. The combined experiences of everyone who has done it is very informative compared to one opinion, as it is with everything else.
I do understand your concern about messing up. I was concerned too and was the reason I bought a Riden PS to parallel top balance for my peace of mind. I had thought about buying a 3.65 LFE charger. When I took all of the features of the Riden into consideration it was an easy choice and I have had no regrets. I have used the Riden to improve the delta of my cells, and use it to charge another pack I have. In the beginning I was using it to charge my EVE pack and used a cheap inverter for my capacity tests.
Using a cheap power supply will be just as effective and safe providing one understands the instructions which are also posted in the resources section of this forum. It's not rocket science and doesn't require an EE degree to perfectly parallel top balance and to do it safely.
Regarding
@Will Prowse, maybe at the time he made that comment he did not know to set the power supply to 3.65 volts before connecting to the cells. It's easy to miss that part.....too easy. Will isn't infallible, none of us are and neither are any experts. No one is perfect all of the time. I would like to know what he was concerned about. I have not heard of any of the cheap power supplies deciding to do bad things on their own.
I will say again, no one is suggesting the voltage should not be monitored at the cells terminals towards the end of charge. You seem to be well versed enough with electronics to be able to build a HVD or HV alarm.