The two good designs connect the output to the long-tail phase splitter to bring the two output tubes into identical functioning. The example below converts the top tube into a grounded-cathode amplifier by relaying any signal at its cathode to its grid, eliminating the degenerative feedback that would otherwise occur and create cathode follower functioning.   

Getting back to SRPP
    Now that we have seen how push-pull is done on the expensive, how do we move back to the frugality of the SRPP, without giving up too much of the expensive version's better performance? The first step is to try to eliminate as many coupling capacitors as possible.

    In the above circuit, we see a bootstrapping capacitor connect the output to the phase splitter. (Bootstrapping implies positive feedback and in effect that is what this capacitor accomplishes in this circuit. In the following circuit this capacitor results in negative feedback and thus should not go by the bootstrapping name.) So arranged, the grid follows the cathode, undoing the degeneration at the top triode's cathode, resulting in both voltage gain and a higher output impedance (and greater distortion).
     The circuit below moves the capacitor's connection to the other phase's leg, resulting in the top triode's restoration as a cathode follower and the bottom triode's conversion into a cathode follower.   

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