Tryndamere might actually be able to team fight with these runes and item changes
Consider this:
- 30% tenacity from mercury treads
- 35% tenacity from perserverance rune (10% for each summoner spell on cooldown, 15% for 10 seconds after using one)
- 20% tenacity from legend tenacity rune (5 stacks)
- 30% tenacity from sterak's gage (for 8 seconds after taking triggering lifeline)
stacking multiplicatively that makes:
1 - 0.7 * 0.65 * 0.8 * 0.7 = 74.52% tenacity for longer than the duration of his ultimate.
If you take cleanse as a summoner spell you could have
1 - 0.7 * 0.65 * 0.8 * 0.7 * 0.35 = 91.08% tenacity for the first 3 seconds.
So something like morgana binding would only last for about 0.75 seconds rather than 3 seconds, or for around 0.3 seconds during cleanse tenacity boost.