RD, the convertible is what impacts weighted average of the diluted shares, and is not included in the O/S until the time of conversion.
With regard to collateral shares, if and when assigned to the treasury, they are taken out of the O/S count, and not returned to the O/S until such time they're "reissued", if ever. While in treasury they are void of dividends paid, voting rights, etc.
Also, weighted averages are calculated/factored by the number of days remaining in the fiscal year. e.g. 10 shares issued on January 1, 2016 would carry a 10 shares weighted average throughout 2016. otoh 10 shares issued July 1 would carry a 5 shares weighted average throughout the remainder of 2016. When January 1, 2017 rolls around, all shares issued during 2016 then are weighed at 100% of value.
Hope this helps.