multiple e-mail addresses: what are the solutions?

[gerry_lowry (alliston ontario canada)]

Thank you John and David.

John Clizbe has suggested a "key with multiple email addresses (userIDs) per identity/personae"
as one strategy.  David Shaw has mentioned a strategy of separate keys for different purposes.

My question:  if I go with separate keys, as in

      e-mail_address_1          public_key_1        private_key_1

      e-mail_address_2          public_key_2        private_key_2

      e-mail_address_3          public_key_3        private_key_3

then, is it permissible to have
all of my public keys together on the same pubring.gpg file and
 all of my private keys together on the same secring.gpg file?

is it even architecturally possible to have
all of my public keys together on the same pubring.gpg file and
all of my private keys together on the same secring.gpg file?

Also, if it is possible, what are the advantages and the disadvantages?

Thank you.

Regards,
Gerry (Lowry)