There are two ways to look at this pairing. The more cynical view this pairing as nothing more than the machinations of Hello! Project and two young girls to build popularity among previously unknown members. I was onboard in January 2011 when these two girls became part of Morning Musume, but I assume many people were lamenting the loss of Kamei Eri, Jun Jun, and Lin Lin to really invest into the Qki generation. Also, some fans might have been too heavily invested in their Oshi to really care about a new generation. Maybe some people didn’t even care about a new generation (I have some choice words for these people).
When Mizupon and Eripon teamed up, it was magical. The girls now had foils with which to play to their strengths. Mizuki may have been talented and pretty, but she was shy and soft-spoken. Eripon also needed someone to help her break out of her shell and take attention away from her AKB wota-dom. And PonPon was born!
Of course the cynical view is that of two girls who are similar in age, in new surroundings, and have similar opinions on fandom met each other and became friends. I don’t know about you, but doesn’t this seem more in character with 14 year old girls than the manipulative scheming that some would have us believe?