It is belief in God that is paramount. We do not worship Baha’u’llah or Moses or Krishna. We only worship God.
This is what I'm looking at:
We must not be rigid about praying; there is not a set of rules governing it; the main thing is we must start out with the right concept of God, the Manifestation, the Master, the Guardian -- we can turn, in thought, to any one of them when we pray. For instance you can ask Bahá’u’lláh for some thing, or, thinking of Him, ask God for it. The same is true of the Master or the Guardian. You can turn in thought to either of them and then ask their intercession, or pray direct to God. As long as you don't confuse their stations, and make them all equal, it does not matter much how you orient your thoughts.
Shoghi Effendi, Lights of Guidance, p. 456
We pray to God, or to Bahá’u’lláh, as we please. But if in our thoughts we desire to turn to the Guardian first and then address our prayer, there is no objection, as long as we always bear in mind he is only the Guardian, and do not confuse his station with that of the Prophet or even the Master.
Shoghi Effendi, Lights of Guidance, p. 457
You have asked whether our prayers go beyond Bahá’u’lláh: It all depends whether we pray to Him directly and through Him to God. We may do both and also can pray directly to God, but our prayers would certainly be more effective and illuminating if they are addressed to Him through His Manifestation, Bahá’u’lláh. Under no circumstances, however, we can, while repeating the prayers, insert the name Bahá’u’lláh where the word 'God' is used. This would be tantamount to a blasphemy.
Shoghi Effendi, Lights of Guidance, p. 457
So even if it is not done in practice anymore or in your community, it's still allowed to direct prayer to either Baha'u'llah, Abdul'Baha, or Shoghi Effendi. That's a violation of the ten commandments ( "You shall not have any other divine power in front of me" ).
So you see, it's not just clergy, or clinging to interpretations. Following Baha'u'llah directly violates the text. If you want to claim that the text has been corrupted, that's a different story. But I'm pretty sure that Islam would prohibit praying to manifestations as well and it's text is supposed to be perfect per Baha'i standards?