Mueller pronounced the homophony of -st st- in 26 to be 'unmöglich', which PHI shows not to be quite the case, but it comes close enough to be an important factor: This would be the only instance in H., it is absent from Virgil (Aen. 7.552-3 abunde est: / stant, with line-end and strong punctuation, the only one such instance, is less offensive), Catullus has one example (78.5 Gallus homo est stultus, where the offense and the effect may be deliberate), as does Lucretius (5.1365), Propertius has two (2.34.53; 3.15.30), Tibullus, none. Ovid is fairly unconcerned, with eleven instances (Her. 15.1; 19.146; Ars 2.444; Rem. 207; Met. 3.186; 4.300; 6.55; 8.451 (across line-end); Fast. 5.448; Trist. 2.1.257; 5.12.62), Lucan has three (3.461; 6.378; 8.592), Statius, one (Ach. 1.600). It was also avoided by prose authors, Livy, for instance, having only ten examples, with intervening punctuation in all but three cases. (Richard F. Thomas's commentary on Horace's fourth book of odes and the carmen saeculare, Cambridge University Press 2011.)
PHI: Packard Humanities Institute, CD ROM 5.3 c. 1991.
I must be deaf, "st st" never offended me.