Sergei Ponomarenko is not 1.73 m he is 5.8 which is about 177 cm. I think being short (under 170 - 173 cm) is a disadvantage in ice dance.
Umm, no. 5 foot 8 inches is equal to 68 inches. 68 inches is equal to 172.72 cm, which gets rounded to 173 cm or 1.73 m. Shane and Jean Luc are 5'7", which is equal to 170 cm.
177 cm is a 69.7 inches, or a bit over 5'9.5".