Recently I stumbled upon this passage:
[...] 最高執行責任者は変化の兆しを語る.
The dictionary reports four readings for 執行: しぎょう、しっこう、しゅうぎょう、 and しゅぎょう。
Moving on with the reading I also found the word 執行役員 that apparently is read しっこうやくいん. This makes me think that even in the above case しっこう could be the right choice.
Actually (instant edit) I just now found that 最高執行責任者 can be translated with COO and it is indeed read as さいこうしっこうせきにんしゃ. Somehow I answered my question by myself then, and しっこう seems a common reading.
Rather than deleting my post though, I got curious and I would like to know if someone could provide words where actually one of the other readings is used..otherwise why are they so many?
Also, let me to use this example in order to ask a more general question. I guess we all agree that the 読み方 of some kanji sometimes follows no special rules and you just "have to know it". However, is this really always the case? Are there any tricks that at least might increase the chances of guessing the correct/most appropriate reading? Thanks.