In these situations, acid treatment would normally cause the alkene to become protonated, moving the double bond to the carboxylic group, changing it to a hydroxy group.
The same as ring system, corrections have been made to other situations such as Gauche alkane with a 0.8kcal/mol correction, cis alkene with a 1.0kcal/mol correction, respectively.
The most common example is E-stilbene, which upon irradiation undergoes an E to Z isomerization, which can be followed by a 6π electrocyclization.
The McMurry reaction, in which two carbonyls are coupled to give a single alkene
Vilarrasa and Costa’s group hypothesized that radical reactions producing HI and I2 help facilitate cleavage in alcohol’s protecting group and may add into other alkene bonds.