A follow up to this earlier post on LTE and capacity: Every now and then I see a debate of whether it is better to upgrade from HSPA to HSPA+ or to go to LTE. From a capacity point of view I think it's not an "or" decision, it's rather an "and" decision.
I don't see a reason why operators using LTE as a capacity extension in the 2.6 GHz band should not also upgrade to HSPA+ (before, after or at the same time) to make the best out of of the 2.1 GHz spectrum as well and to support as many HSPA users as possible. True, not all mobile devices will be HSPA+ capable for quite some time, but HSPA+ is backwards compatible thus taking everyone forward.
Especially once current equipment is end of life and replaced by multi-technology and multi-band base stations, potentially with new MIMO antennas that can be used simultaneously in the 2.1 and 2.6 GHz band, it seems rather a natural thing to do to me.
As always, thoughts are welcome.