I could use some feedback on the below. Thanks in advance

Account owner is age 73, not married, NY resident, living with non-spouse partner.

Account owner wishes to share proceeds of IRA with daughter and partner.

Advice of attorney is to change existing IRA beneficiaries (required minimum distributions began in 2002) to 50% to the daughter and the remaining 50% to the estate so the non-spouse partner can receive his share.

Is this plan the most tax-efficient way to accomplish the stated objective? Wouldn't the inclusion of the estate impact the daughter's ability to stretch out?

My thought is that naming the estate will result in a lump sum distribution with a large tax bill. If instead the individuals were named, they could take distributions based on RDM requirements and stretch out payments, thereby (potentially) lowering the tax bill

If the daughter and the estate are name as beneficiaries, the daughter would be able to use her life expectancy if the estate distributes its share by September 30 of the year following the year of death…or if the assets are segregated into separate inherited IRAs by December 31 of the year following the year of death, the daughter would be able to use her life expectancy and the estate would be eligible to use the remaining life expectancy of the decedent.

If both individuals are designed beneficiaries, each could use their one life expectancies if the assets are segregated into separate inherited IRAs by December 31 of the year following the year of death…unless the partner is older than the IRA owner, in which case, the partner would use the remaining life expectancy of the IRA owner.

I am not qualified to address the issue of which is better from a tax-perspective.

Thank you. I had thought naming a non-natural person (such as the estate) as the beneficiary was NOT ideal if the goal was to pass the assets to natural persons (named in the will), AND, allow the natural persons to use their life expectancy(ies). I suspected the attorney did not consider the distribution implications when suggesting the estate be named the sole beneficiary of the account. I appreciate the confirmation.