Cisco ISR routers and etherchannel oddities

I've been playing around with etherchannel from a Cisco 3925 router (IOS 15.7(3)M3) to a Cisco 2960X switch. Researching this, the docs say that the ISR routers only support raw etherchannel - no LACP or PaGP.

Ok, so I set up my port channels on each side and everything seems to work. I can pull either cable of the port channel and things go right on ticking.

The two oddities I've noticed:

1. When doing a "show ?" on the router, I see a "show pagp" option. That seems to run contrary to the docs specifically stating PaGP is not supported.

2. On the router, a "show etherchannel" shows zip, regardless of any options to the show etherchannel command. If I do "show etherchannel {whatever}" on the switch, I see the results I expect.

Is the "show pagp" command on the router just a vestigial bit in the IOS code from some other device?

Is the "show etherchannel" command just broken?

Relevant router config bits:

interface Port-channel1 description Uplink to switch no ip address interface GigabitEthernet0/0 no ip address duplex auto speed auto channel-group 1 interface GigabitEthernet0/1 no ip address duplex auto speed auto channel-group 1 

Switch config

interface Port-channel1 description Router switchport mode trunk spanning-tree portfast interface GigabitEthernet1/0/20 switchport mode trunk spanning-tree portfast channel-group 1 mode on interface GigabitEthernet1/0/24 switchport mode trunk spanning-tree portfast channel-group 1 mode on