If play 4th suit double,I should make double instead of 2♥ here.
Now I strongly suggest Gib should play 4th suit double.
The basic meanings :
1- Pass = weakish hand
2- double = promises 5-card ♥ with ♦ support.
3- raising to 2♦ = deny 5-card ♥ .
4- bidding 2♥ = 5-card ♥ without ♦ support.
Any idea?