Because RMDs are not eligible for rollover, TurboTax ask how much is RMD (a required distribution) only to determine how much the distribution exceeds your RMD and is eligible for rollover. If you roll over any part of a required distribution, TurboTax must treat that as an amount not rolled over and it becomes an excess contribution in the account that received the rollover. As VolvoGirl said, regular periodic pension payments (received as an annuity for life) are not eligible for rollover, so the entire amount of these pension distributions is considered to be a required distribution and is ineligible for rollover.
Pension distributions are not permitted to be treated as satisfying any part of an IRA RMD. Your RMDs for your traditional IRAs are only permitted to be satisfied by distributions from your traditional IRAs.
