When I sing "Farewell to Tarwaithie", I use the last line of "Crimmond" (The Lord's my Shepherd) as a link between verses. Crimmond is mentioned in the first verse, so it seems appropriate - I think Tony Rose did the same thing.

In "Mrs Merry's Ball" Muckram Wakes use "Winster Gallop" in the middle after the line "The dancing did begin." It provides a useful break before the last (slow) verse.

If a tune works, doesn't spoil the continuity, and adds something to the overall performance, why not use it ?