I am in a similar position to the original letter writer to Mr. Pape, a 30+ year CDN employee who slowly acquired shares thru DRIP.  

A couple other  considerations-
1.  the complex calculation of adjusted cost base over time (stock price, stock splits and especially the US/Cda exchange rate fluctuations over 30 years)
2. the safety of the dividend - IBM cut it's dividend in tough times in the past, it may do so again.
3. the company's future is complicated - it has seen decreasing revenue for 4 straight years under CEO Ginni Rommety (i.e. from 100B to about 80B in 2016) - 5 year return is down over 21%. Rometty's departure would be positive (financially and for employee morale), but there would be uncertainty as well with the new guard
4. in my opinion, most employees are extremely pessimistic about the future growth of revenue - the I/T competitors are very nimble and lean now and it's difficult to imagine a future where IBM can significantly ever grow revenue again.